: Lifter starting to tap and needs replacing,

06-30-09, 01:32 PM
this is a continuation from another thread that I started "grinding noise" which was another problem although this problem started while I had the other thread going.

I started to get a tick in my engine but it would only tick about 2-3 seconds at idle and then it would go away for about 6 seconds. This pattern was repeated over and over where the engine would be quiet at idle for about 6 seconds and then tick for about 2-3 seconds. This went on for about a week, maybe 10-15 miles of driving and then it started to tick all the time once the engine was warm. When First started there is no noise but when it warms up, the ticking starts. I changed the oil twice and the second time I used fleet oil like Submariner mentioned and it made no difference. I see nothing in the oil or filter, clean as a whistle.

I now removed the cam cover on the front bank suspecting that a lifter if bad would be the #8 exhaust. All of the lifters look like mirrors, not a scratch or any imperfection that I can see. The timing chains that I can see look good along with the tensioner. I can't see under the cam lobes but I doubt there is anything therefrom what I can see now. Can I loosen the cam caps and lift the cams just a bit s I can see underneath? Does anyoine knoe the torque spec's for the cam caps? I know I need to keep the cam timing unchanged so I would mark the position of each in the event something moved.

I tried to attach a picture last night but somehow lost my post so I'm not going to try that again for now.

Any suggestions on where I go from here other than remove the cover on the rear bank.

A local Cadillac mechanic who has worked on cadillacs for years said they have never changed a lifter on a N*. From reading here, it seems like there are a lot of lifters being worn out and changed.

Another important note, the tick had turned into more of a tap when I decided to remove the cover, it's no longer a light tick rather a pretty good tap, it seems like something would show on a lifter or cam lobe!

Any suggestions or comments would be appreciated!

06-30-09, 01:49 PM
Lifter-wise, nothing to add to my previous posts. Eyeball each pair of cam lobes (2 intake and 2 exhaust lobes) for each cylinder. Are they all matched for tip height, i.e. one lobe of a pair doesn't seem more "rounded off" ??

While you're in there, pull the plugs and see what they look like. All in one piece, no pieces of electrode missing ? Tips light gray to brownish gray ???

06-30-09, 02:04 PM
Submariner, do you know if the two lobes per cylinder are timed the same, for example do both of the exhaust lobes for Cylinder 8 open and close at the same time, they appear like they do but there could be soem overlap. The only thing I noticed is that the very last lifter, when the valve is fully opened, looks like it's down in the bore about 1/32" from the top of the lifter boss. The other lifter from the other lobe appears to be flush with the lifter boss just like all of the lifters from the other cylinders.

It could be the way the head is mchined and means nothing but it is down below the top of the lifter boss if that means anything. I guess these lifters can collapse and of course not running and sitting, it could've went down that little bit. The lobe for that lifter looks good as does the lifter. I didn't drive it very much, maybe not even 10 miles so there may not be any visual signs.

I'm going to attach a picture here in a bit.


06-30-09, 02:16 PM
Both cam lobes on any cylinder - intake or exhaust - are machined for identical lift and timing.

Not sure about the possibly recessed lifter - if that cam lobe was worn the lifter would not go as far down in the bore..........

06-30-09, 02:31 PM
Submariner, If all of the lifters were good, that is the surface that's good but one of them for one reason or another is collapsing enough to make the tapping noise, do you think that with about 20-30 minutes of run time there would be evidence of which lifter it may be.

I'm thinking that I haven't driven it enough for any physical damage to show up yet and how would you know which lifter is collapsed?

I know I'm getting ahead of myself because I still have the back bank to look at but, in a way, I'm discouraged thast I didn't find something on that front bank.

06-30-09, 03:46 PM
Does anyone know if the back cam cover is harder to get off than the front cover or is about the same amount of work. That front cover wasn't that bad but it wasn't that easy either. I guess what I want to know is will I have to loosen a motor mount to remove the back cam cover? I'm getting older and it's hard staying bent over these cars for a significant amount of time!

06-30-09, 04:17 PM
I attach a file and it shows up like this...50929

06-30-09, 04:19 PM
My god, it worked, here are the rest!50930






06-30-09, 04:37 PM
Maybe something inside the lifter was damaged and is making the tapping noise....?

The rear bank is harder because of the coolant pipes that run back there. They have brackets attaching them to the valve cover. Also the main wiring harness is back there, probably in the way.

Camshaft bearing caps are 106 inch lbs.

06-30-09, 04:56 PM
The only thing I noticed is that the very last lifter, when the valve is fully opened, looks like it's down in the bore about 1/32" from the top of the lifter boss.

Could this be a bent/sticking valve keeping the lifter from coming all the way back up?

Edit, sorry, I didnt read that right the first time, I was thinking this was with the valve closed.

06-30-09, 11:19 PM
These are the two best pictures I could come up with, no matter how I turned them the light would reflect back into the camera lens. I tried two different cameras and still these are terrible pictures.

This is the last exhaust lifter from cylinder #8. There is a groove in the middle the width of the cam lobe, disregard the grainey surface, that's the camera. It's obvious this lifter quit turning in it's bore therefore the groove in the middle where the cam lobe rides. There is an indentation maybe five thousands of an inch, not much but it's really the only sign of a problem.



06-30-09, 11:29 PM
In the prior post, the picture with the car in the background shows the indentation the best.

This is what I decided to do before taking the back cover off, remove the cams in the front so I could get a better look at the lifters. In doing so, I see that exhaust lifter is aproblem, may not be the one that started tapping but then again it could be. I'm going to replace that lifter and out the cover back on, start the engine and see if the tap is still present, if it's gone, great, it as that lifter. If not, then I remove the rear cover and go from there.

I'm almost convinced that the lifter with the indentation is the problem. It appears that it quit turning and maybe could've pumped down which in turn caused the indentation from the tap I was hearing. I took a wrench and tapped this lifter on the bottom with a cloth around the wrench, of course I tapped on a non contact surface area and it sounds just like the tap I was hearing.

Any suggestions or contradictions to what I'm thinking, I don't want to do this again and hope to get it right the first time around!

07-01-09, 12:05 AM
This is a little off topic but I found this interesting. In the last thread I started, I had mentioned I didn't notice any difference in the performance of the engine and that it still would idle like a top, how could I have a bad cam lobe, lifter etc. etc.

I was getting ready to go to bed one night thinking about my problem with the car and I kept repeating to myself, double the valves and double the fun which 97EldoCoupe puts at the end of his posts. That's when I realized or it dawned on me that the N* has 4 valves per cylinder. Even if a cam lobe is ground down to nothing you still have another valve that's operating like it should and that cylinder will still fire pretty decent.

I remember commenting that if an exhaust valve or lobe was gone the engine would backfire through the intake but that's not true with an engine that has 4 valves per cylinder. Sure you would probably hear a loud tap or knock with a lobe ground down or a lifter that's ground down to nothing but the engine will still run pretty darn good and still make pretty good power.

It was that comment from 97 EldoCoupe that got me to thinking about that. I'm old school and the first thing I do is listen to the idle if I have a problem. With an N* you can just about throw the idle procedure out the window if your looking for a valve train problem.

07-01-09, 11:17 AM
rodman, Go ahead and replace that follower (lifter) pair. Be sure to use CompCams, Engle, or Edelbrock cam breakin lube. Better yet, lube ALL the lobes and follower faces before you bolt down the cams.

A local speed shop will have cam lube.

07-01-09, 02:51 PM
I thought it was best to replace the cam anytime a new lifter (set) goes in, and new lifters when a new cam goes in (or replace with a used cam with the lifters that were broken in on it). Is that just belt and suspenders thinking?

07-01-09, 05:05 PM
By all that's Holy, yes, you replace the lifters and cam as a set. BUT, because doing that in a Northstar would require you to apply for your own Stimulus Package, you'll be OK if you fudge a bit. The lifter set alone is some outlandish price, and the cam(s) are worse.

Fortunately the 2000+ engines use roller cam followers with a static hydraulic lash adjuster (not direct-acting lifters/cam followers) so for us, the point is moot........and you can't retrofit the new heads.........

07-01-09, 05:19 PM
Lifter-wise, nothing to add to my previous posts. Eyeball each pair of cam lobes (2 intake and 2 exhaust lobes) for each cylinder. Are they all matched for tip height, i.e. one lobe of a pair doesn't seem more "rounded off" ??

While you're in there, pull the plugs and see what they look like. All in one piece, no pieces of electrode missing ? Tips light gray to brownish gray ???

EDIT....Rodman, go to the UserCP in the blue bar ^^^ and update your login with your car, year, engine, and mileage. It will help to keep everyone on the same page because there are a LOT of differences from 96 - on and again from 2000 - on.

07-01-09, 05:44 PM
Just FYI, I think Jake sells good used cam/lifter sets for much less than OEM. He's the stud kit guy.

07-01-09, 08:24 PM
Submariner, I agree with you about the lifters, sure you change the cam and all the lifters if you have an umlimited amount of money. For an older higher mileage car like mine, a lifter or two will do.

I have run into a problem. I wanted to look at all the lifters on tis bank so I unbolted the intake cam. I wired the sprocket to the chain so I wouldn't lose the position. Now when I pushed the cam back down into position, the chain seems really tight, expecially between the two cams. I doubt I could've moved the chain on the lower cam but to be sure I want to chech the timing marks.

Last night I saw some pictures of the front of a N* with the timing cover off, motor was out of a car. I can't find those pictures, I thought they were in the thread where the fella did a head gasket job in the car and the pictures from krashed or maybe STSS, can't remember.

Any help would be appreciated, I don't mind turning the motor over once or twice if I have to make sure the marks are aligned.


07-01-09, 08:56 PM
Pic is here

Really quick search.... "head gasket in car"

07-01-09, 09:03 PM
There is a chain tensioner. Did you maintain chain tension? If not, it probably extended. I'm not sure how to fix it as I've never had to do it. Someone who has done it will help.

07-01-09, 10:25 PM
Ranger, I did maintain tension on the chain whoever I after looking at the picture again, I think your probably right about the chain tensioner extending while I tilted the cam up.

STSS thanks for the link, I swear I was looking at that thread before I posted that I couldn't find it. I maybe scrolled down to fast and the pcitures weren't through downloading, thanks a million. I feel better now that I looked at the picture. The only thinkg that could've happened is what Ranger mentioned and that is the tensioner extended when I tilted the cam up.

I guess my question is, could that piston on the tensioner have come out of the hole if I had to much slack in the chain. I would think not but you never know. The chain just seems to tight righ tnow but then again I didn't really look at it real close before I started taking the cams loose. I do remember pullingon the chain when I first removed the cover thinking, boy, there's more thension on that chain than I thought there would be, so maybe the tighness is normal.

I've turned the motor over at least 1 revolution with a wrench and sore fingers, 4 loose spark plugs on the front bank and 4 tight plugs on the back bank and I don't hear any popping by the timing chains so everything muyst be okay.

I'm 99.9% certain the chain and sprockets didn't move in relation to each other, like I said I wired the chain to the sprocket so it couldn't jump a link.

Do I button it up and start it or do I wait for one of the engine guys to give some guidance on the seemingly tight chain?

I won't button it up tonight, it'll be in the morning, finger tips need to heel!!

Thanks guys.........

07-01-09, 10:42 PM
I don't think I mentioned it but the intake lifters all looked real good, really no wear patterns to speak of, the only bad lifter in the front bank was that last exhaust lifter which I showed a picture of. I changed those exhaust lifters and lubed up all the lobes and tops of the lifters real good with some assembly lube.

I hope that last lifter was the one that started to tap, I believe so by looking at it but will know for sure when I start it back up!

07-01-09, 11:05 PM
the tightness of the chain might have also had to do with how the other cam probably wanted to "jump". The cams are under spring tension from the valves, so maybe the other cam was putting extra tension on the chain.

And this was my thread with the pic you mentioned in it.

07-02-09, 12:20 AM
Thanks for the link, the pictures actually do help quite a bit at times. Do you remember how tight the chain was from cam to cam, mines pretty tight. I guess it has to be pretty tight or your timing would be off, seems like the tensioner may have came out a bit when I moved the cam as suggested by Ranger. I imagine that the tensioner would reverse itself if to tight once the engine is running, I hope so.

There has to be a way to decrease the tension or you wouldn't be able to get the chains on when the engine together, any help on this subject would be appreciated!

Thanks again everyone.........

07-02-09, 12:36 AM
They compress and decompress like a spring... No ratcheting at all. There is a lock on the side of it so you can compress it and lock it like that for easier installation.

07-02-09, 01:57 AM
Krashed, I guess the consensus is that the tightness is in fact normal. If I grab the chain between the two cam sprockets, it's about what 6 inches of chain, I can barely move the chain up or down. If I were to put a straight edge across the chain, by pushing or pulling quite hard, I might get about 1/16th of an inch play.

It's late and time to get refreshed for another day in the park so I'll check in the morning before I put the mighty N* back together. Really not much to do, put the valve cover back on, the two fans and braket, water pump pulley, tighten spark plugs and plug them in.


07-02-09, 09:26 AM
The cam chains, when the tensioner is properly engaged, will be tight, even on the off-side (The slack side, not the drive side.)

The chain itself bears none of the valve spring tension: that's all controlled by the lobes and cam bearings themselves.

07-02-09, 11:17 AM
I want to make sure I didn't move the timing chain a tooth before I put everything back together.

I'm sure there's a procedure for cheking the cam timing and if anyone knows it off hand, please post a procedure. I'm going to do a search under cam timing and see what I come up with.

For now, I'm going to get #1 on top, not sure on how I'll do that because I'm used to putting my finger in the plug hole and feeling for compression on the way up, I guess I can cover the hole in the cover and I'll get the same effect, should be able to feel the compression stroke.

I thought I read somewhere, when number 1 is up, then the marks on the cam gears would be in the 12 o'clock position.

Any help would be appreciated.

07-02-09, 01:25 PM
Take some paper towels and ball them up. Then stuff the ball into the #1 spark plug hole. When the piston is on compression it will literally shoot the ball out. After that you can stick a screwdriver or something into the hole and touch the top of the piston to see where it is. When #1 is at TDC compression, the timing marks on the cam should be pointed at a 12'o'clock position in relation to the heads (90 degree angle from the valve cover gasket seating surface).

07-02-09, 01:59 PM
I like the paper towel trick, this is where I'm at. I looked at those marks at least 100 times, the marks on the cams. I even took a right angle ruler and lined them up with the top of the head, they are both at 12 o'clock, no doubt. I put the cover back on with a couple of screws and the beauty cover with a couple of screws and started the engine. It started but is loaded up big time. It sounds like I have HP cam with a little overlap at idle and smooths out around 3k RPM's. I didn't run it but maybe 15-20 seconds and a second time the same.

I'm going to see if any codes were set, why would it run so rich? The beauty cover maybe not being tightened all the way around maybe causing a big time vacuum leak?

I'm checking hoses and plugs to make sure I didn't knock soemthing off, once again, any suggestions would be appreciated!

07-02-09, 02:26 PM
The beauty cover is for nothing but an insulator and looks (unless the car is a 94). I hate to say this but, the chain might have jumped a tooth on the intermediate sprocket so both cams are either advanced or retarded. Sounds more like the timing went advanced 1 tooth since you say it sounds like a hot rod..... Next comes the tricky part, how to fix it. I guess the way to go would be to just make the cam sprockets both jump a tooth in the other direction. To retard the timing back to normal, you would need to pull the chain from the tensioner side over the cams 1 tooth. Be careful, I lost some skin from my thumb from attempting this when i was timing my dads engine.

07-02-09, 03:13 PM
Krashed, the car is a 94 Seville STS! I put everything bacl together properly, tightened up the beauty cover and also put the plate with the seal for the water pump pulley back on. I guess without that plate and seal, you have an open hole which I'm sure allows air into the crankcase.

Here's the good part, I started it and it ran perfect right away, idled like a dream. I'm going to go and start it again right now to make sure I'm not dreaming, hang on, I'll be right back,.........pause...........!!

:thumbsup:Still running okay!

Now I'm going to put all the fans back in place, water pump pulley, etc. so I can run the R's up and break in the lifters!

Thanks, I'll be back!

07-02-09, 04:32 PM
Krashed, the car is a 94 Seville STS!

LOL whoops I forgot! :p

I'm glad to hear that it's working properly though! Is the tapping still there?

07-02-09, 05:25 PM
To break in the new lifters take the car out for a half hour highway run. DO NOT idle it more than absolutely necessary. You WANT the engine to stay over 1,500 rpm for a while.

07-02-09, 07:26 PM
Sorry it took so long to get back, I had several errands I had to run, been getting behind working on this car of mine.

It runs good but unfortunate;y the tap is still present. As soon as it warmed up it started the same tapping so I guess the problem is in the back bank. Submariner, I was keeping the R's up there while it was warming up but then the tapping started and I pretty much shut it down within a minute so I really haven't had a chance to break in those lifters.

I'm quite certain that the front bank is good, there has to be a lifter on that back bank that is pretty bad. I figured it wouldn't hurt to look at the front bank and replace anything that looked suspect hoping that the problem would be corrected, you win some and you lose some.

Other than a lifter, what can make a tapping sound, I could see down into the front of the timing chain case and everything looked good.

If I do anything I'm going to have to let my hands heel first, a couple of fingers are also tore up and half numb.

Krashed, curious why you said unless you have a 94, what's the difference with that year versus other years?

I'll be here, thanks everyone, I appreciate the help/comments/support, you name it, thanks!!!

Submariner, I'll take the time later tonight to enter the info you mnetioned.

07-02-09, 09:13 PM
My 2002 had a tapping sound at idle that I knew was a lifter having bad lifters in the past GM cars. Wrong....It was piston slap. Dealer replaced pistons with new ones that have a teflon pads on the piston skirt. Also they installed new oil rings that stop the carbon fouling from oil and stopped all oil usage between oil changes. Use to be a quart down at 50%. Now no oil usage between oil changes. If you have carbon build up on piston it causes a ticking sound as piston hits carbon/head and tilts/slaps cylinder wall. Sure sounded like a lifter to me...:thepan:

07-02-09, 09:15 PM
Krashed, curious why you said unless you have a 94, what's the difference with that year versus other years?

Well in 94 the cover was actually a functional part of the intake. The whole thing was a plenum and a backfire valve (the whole thing would lift up in the event of too much pressure). If you were to start the engine with it off, the rpms would be unthrottled and would bounce off the rev limiter. In 95 cadillac redesigned the intake manifold to gain a better air/fuel mixture. The air ducts were sealed and vacuum hoses were added to whatever needed them. The cover was still put in place though as a decoration and also as a heat sheild so the engine heat wouldn't discolor the paint on the hood (mostly as a decoration though). You can remove the cover and drive around without problems on a 95 or later model cadillac.

07-02-09, 11:27 PM
Tonkin, funny you say that, I was just sitting hear thinking what can male a tapping noise in an engine. I'm thinking in the case of N* which has the overhead cams, not much, a lifter/cam lobe or a rod bearing. Now a main bearing can make a faint knock, a rod bearing can make a pretty good knock once it starts grinding down but neither of those I would consider a tap, more of a knock.

I was even thinking maybe the starter has a broken ear/bolt and soemthing is hitting the flywheel when it warms up. Now, that's really stretching it but I can't think of anything other than what I've mentioned that can make a tapping noise. I didn't even think or consider a piston slapping the cylinder wall but I'm sure it's possible. I haven't read anything on this forum about piston slap with a N* so i woudl say it'spossible but remote. I do appreciate the thought and if the problem doesn't show up in the back bank, maybe it'll be time to go into the bottom end which I won't be doing, getting to old for this!

Krashed, thanks for the info on the 94 N*, apparantly GM engineers were still in the trial stage at that point but were under pressure from the powers to be to release their car/N* to the public! Only kidding!!

Thanks everyone, we'll get it sooner or later, one way or another:D

07-06-09, 08:29 PM
My hands finally heeled enough and I recharged enoughed to get the back cam cover off and found the lifter on the left side of the picture to have a punch mark near the center or you could say the skin has been broken on this lifter, laft exhaust lifter on the back bank. The lifter next to it is the last exhaust from the front bank.

I have more to say or aks but I want to see if the pictuer shows up first so I'll post agin in a minute.

07-06-09, 08:47 PM

I see the picture didn't show up so I'll try again! I believe I got it this time, hope it's clear enough to see the indentation. I see the picture will show this time, the lifter on the left has the skin broken so I'm pretty sure that's the lifter that started to tap, couldn't fins any other lifters that showed and wear, they all looked real good IMHO for an engine that has just over 100k miles.

As it is I'm going to repalce that last lifter again although this time it's on the back bank, quite hard to get that cam cover off, very hard indeed, probably wouldn't do it again.

A problem that I ran into is similar to the problem I ran into when I did the front, the timing chain tightened up when I lifted the fron of the cam and now I can't get it back into postion. When I used to work on cars I was in the habit of double and triple checking, that also meant I had to see it with my own eyes. I had lifted the cam enough where I could see the tops of all the lifters okay, just like I did the 3 previous times with the other cams. Apparantly this time I lifted the cam a little to high on the gear end and it came out of it's cam bore which allowed it to move over some I guess from the chain tightening up.

How can I get that cam to move back over about 1/4"-3/8" if at all possible. Please don't tell me I'm going to have to remove the front of the motor to get at the timing chain tensioners to replease the tension. I guess if I have to I have, it is what it is.

Looking for comments on the timing chain tensioners and how can I release the tension on the chain.

On a positive side, this is the first lifter that looks like it's been hit or tapped on by the cam. I guess I'm going to have to find a set of micrometers so I cna check that last exhaust lobe.

07-06-09, 09:07 PM
Did the chain jump?.... if the chain is in the right spot, you should be able to turn the cam with an adjustable wrench on the hex area.... If the chain is too tight, try turning the crank backwards an 8th of a turn. Keep tension on the chain though. If all else fails, put bungee cords through the holes on the cam sprockets, undo the bolts, then bolt down the cams separate from the sprockets. Afterwords you should be able to bolt the sprockets back on. It will probably be a pain in the butt though.

07-06-09, 11:18 PM
Krashed, The intake cam is still bolted down, I had looked at it first and all the lifters looked okay so I bolted it back down and then went to the exhaust cam, I lifted it from the end opposite the sprocket of course and carefuly lifted it until I caould see the tops of all the lifters when I decided to go just a bit higher the sprocket end came out of the bearing boss. I had wired the srpocket to the chain so it hasn't moved in relation to the crank or other cams.

I like the idea about turning the cam bolt and or turning the crank backwards a bit. I thought I read where the chain tensioners were some type of ratchet mechanism where it locks in when it comes out so that it can't go back in unless you release some mechanism to allow it to go back in. If that's the case and the tensioner came out, I'm not sure I can get enough slack in the chain to get the cam back into position. The chain is tight now and it seems like I would have to get the tensioner to back off to get the cam back into position.

If there isn't some locking mechanism on the tensione then I should be able to get the cam back into position.

The picture I posted for the suspect lifter isn't very good but it's the only lifter I found that had the surface compromised, therefore I believe replacing that lifter will eliminate the tapping that just recently started!

07-06-09, 11:31 PM
Hopefully that lifter didn't damage the cam too much.

The tensioners don't ratchet, so you don't have to worry about that. They act just like springs, except that they get harder when the oil pressure goes up. If you move the lock into place it will ratchet in the other direction so you can compress it more without it popping back out.

If you have a long screwdriver you may be able to pry on the tensioner to compress it. Just pry using the chain so you dont mar the chain guides.

07-07-09, 12:10 AM
Krashed, thanks, that's what I needed to know, if I could somehow pry the tensioner back in so as to create a bit more slack in the chain and allowing the cam to move back over that 1/4". I'll give that a try in the morning, if it works and I can get the cam back into position I believe I'll be good to go. I'm going to check the lobe from tha lifter that I'll be changing but visually, it looks fine. It's still prety mcu shiny looking with no scuff makrs so I would guess that the lifter must've collpased a few thousands if that's possible.

The cam definitely started to beat on this lifter, why? The lifter looks like it may be worn a couple of thousands at the most. The lobe looks okay but until I measure it, I won't know for sure. Could the lifter have collapsed? I'll check the valve springs, I assume they are at least double springs, maybe a spring has broken on that lobe. You have to figure to develop a tap, the clearance or spring pressure has been compromised. The lifter must be able to absorb or make up a few thousands of an inch just for wear! I wonder how much tolerance is built into these lifters and where did I lose the maximum tolerance so that the lifter now taps?

Did any of that make any sense to you, or did I not explain my thoughts properly?

07-07-09, 12:28 AM
If I understand the timing chain tensioner properly, it has a locking mechanism used to hold the plunger in while assembly is taking place, (must have a small interanl spring for installation) when released the shoe will come out from the oil pressure. Other than the locking mechanism, there is nothing that will stop it from going back in other than the oil pressure. So in theory, If I drain the oil, there will be no pressure and I should be able to push the shoe back in thus creating slack in the chain.

Comments, corrections?

07-07-09, 01:57 AM
When I was playing with it while cleaning it before re-installation it was still springy. I could compress it with 3 fingers though. When I first took it out there was sill oil in it and it was a little harder to compress, but I could still compress it. I think there is an actual spring inside pushing it out for I guess the minimum tension needed on a dry start before oil pressure goes up.

07-07-09, 03:34 AM
Krashed, appreciate the comments and support, have a good night. I see your in Hawaii so I guess your a few hours behind, still it's probably pretty late, I'll keep you posted on my progress!

07-07-09, 03:20 PM
If I understand the timing chain tensioner properly, it has a locking mechanism used to hold the plunger in while assembly is taking place, (must have a small interanl spring for installation) when released the shoe will come out from the oil pressure. Other than the locking mechanism, there is nothing that will stop it from going back in other than the oil pressure. So in theory, If I drain the oil, there will be no pressure and I should be able to push the shoe back in thus creating slack in the chain.

Comments, corrections?

WRONG! YES they DO ratchet out, and you need to depress the plunger, then put a paper clip in hole in the the lever on the side to hold the plunger in, then install the chain/cam gears/guide, THEN release the plunger.

Think about it: The ratchet action is to keep the chain somewhat tight when the the engine is turned off, so when you start it next time, the chains won't jump the sprockets. SPX sells a special tool to keep the plungers depressed when doing this kind of job. If your plunger is overextended, there is nothing you can do but remove the front cover and press the release lever to allow the plunder to retract; somebody wrote that he did that without removing the balancer - just unbolted the cover and slid it forward on the crank snout enough to reach in and depress the ratchet release lever.

If you force the issue and somehow get the chain installed on the cam gears, you will be putting tremendous pressure on the chain and all the other components including the chain guide, chain tensioner, intermediate gear, cam gears, cam, and cam bearings. You could easily break something and have a much bigger repair job. Do it right and release the tension on both chains and then allow them to re-set - that way you will know you did it right and nothing is going to break.

07-07-09, 04:32 PM
Tateos, thanks for the correction! I agree that if the chains were forced and to tight it could and probably would cause other problems. I haven't looked at it yet today but will be doing so pretty soon. I kept pressure on the cam/sprocket/chain when I lifted it so I don't really see how the plunger could've come out but then again if there was even a small amount of hydraulic pressure on that plunger, it probably came out some. I didn't hear any clicks so maybe I'm still okay, if not, I guess the cover is coming off. I've been asking questions all along and it would've been nice to know that there is a tool to assist in this type of repair, so it goes.

Could it be that there are different type tensioners since Krashed said he was able to depress his when had them in his hand? How could he depress them if they were locked in when they ratchet out? I'm not doubting what you are saying, I'm just gathering all the information I can to make this as easy as I can!

Thanks for the comment/correction!!

07-08-09, 12:08 AM
Made a somewhat feeble attempt to get the cam back in position this afternoon to no avail. I put a little pressure on the chain tensioner to try and get it to retract, no luck. I didn't put a lot of pressure on the tensioner but wouldn't want to put anymore presuure than I did for fear of damaging some component of the timing chain tensioner. Looks as thopugh the timing cover will have to be removed which means a lot of other things will have to be removed.

My motor needs a small oil leak or two repaired so is this the time to do it since half the motor either is or will be apart. The oil leak looks like it's the oil pan and or maybe a rear seal. From underneath, the motor looks dry above the oil pan, looks dry from the half block on down until you get to the oil pan. All that doesn't matter if I have the motor removed to put the valve train back together, all new gaskets and seals will fix the oil leak/seap.

If I can get the timing cover off easy enough I'll put it back together as is, if the timing cover becomes a real pain, I'll have it towed to a shop and have the motor removed & repaired.

07-08-09, 04:53 PM
Does aqnyone know what the timing chain guide access plugs located in the front of the cylinder are for. I know, kind of slef meaning, they are to gain access, for what though? Is there a way to get at the tensioner through one of these access plugs, are they there just for a visual inspection of the timing chain guide?

Right now I'm looking at taking the front of my motor apart to remove the timing chain cover, obviously I'm trying to avoid this, I'm getting a bit old for this type of work!

07-09-09, 12:51 PM
The plugs are for access to the bolt that holds the top of the guide affixed to the block. They actually bottom and have a machined shoulder that allows the tensioner to pivot as needed. I say definitely take them off and see if you can access the tensioners, but I think they are too high up to help. All you need to do move the little lever on the tensioner to allow the piston to retract. You may need an allen wrench to remove the lplugs, but when re-installing the plugs, I think they pretty much just go on finger tight.

07-09-09, 04:10 PM
Interesting.... Maybe they are different? The ones I was working with didn't ratchet out (was for my dads 99 eldo). The lever on the side, when you moved it, it simply engaged a ratcheting mechanism and locked the plunger in place so it wouldn't go out.

07-10-09, 12:12 AM
Krashed, I'll let you know about the tensioner as soon as I get at it. Looks like to remove the power steering reservoir/pump, you have to remove the pulley first, to remove the pulley, you have to remove the filter/dryer for the a/c and or the coolant overflow tank. From what I can see, it appears if I can remove the power steering pump and get at the timing cover, there's enough room to get a couple of fingers behind the timing chain cover and push/pull the lever to release the plunger on the tensioner.

My body/hands have heeled enough so I cna start again, maybe I'll make some progress with this nest attempt.

I believe I asked opinions about the lifters and how much "clearance loss" is built into the lifter, being hydraulic, they could make up for quite a bit of clearance loss, or so you would think. I checked a new lifter alongside an old lifter and it's about .004" taller so one would assume that the old lifter is worn about .004". To really measure the difference you would have to have a micrometer because the valve/lifter contact point is recessed on the bottom of the lifter. The difference that I measured could be the difference in the machining of the replacement lifter and the way it's machined versus OE lifters.

Assuming there is .004" wear on the lifter, I would assume the cam is worn just as much, if not more, that would add up to .008"-010" of clearance loss prior to getting a tapping noise from your motor. This is assuming that the lifter I'm replacing is what was causing the tap to begin with.

I've looked at these lifters quite a bit and don't see how they act or work as a hydraulic lifter, maybe they're not hydraulic, just curious....

Tateos, thanks for your replies, I encourage everyone's opinions and different problems that they've overcome. I like as much as info as I can get even if some of it contradicts earlier or later info. I would rather have to much and have something to sift through versus 1 comment that I know may not be correct or may not apply to my own personal mechanical problem(s)!

Thanks to everyone.......

07-10-09, 03:49 AM
To remove the powersteering pump, empty the reservoir with a turkey baster. Then disconnect both lines at the pump (the solid line you may need to unbolt a 10mm clip from the rear cylinder head). Then look down in between the pump and the rear cylinder head; there is 1 bolt (I think 13mm) holding the pump in place. If unbolting the clip for the solid line didn't give you enough play in the line to take it off, try moving the pump around when it's unbolted. Other than the power steering pump you may have difficulties because of the two coolant pipes. You may be able to get around them by simply rotating the timing cover clockwise though.

I wonder if the "tapping" noise is actually caused by there being too much valve lash, or whatever you would call the gap between the lifter and the cam. Maybe the tapping comes from the cam simply hitting a different texture (one that's not so smooth)?... Just thinking out loud.

Yeah, thanks Tateos for correcting me. I don't like giving out the wrong information. Plus I'm still learning here too.

Let me see if I can get you a pic of the bolt i was talking about for the PS pump.

Edit: Bolt #20 is the bolt I was talking about. It should be the only bolt you have to remove.

07-10-09, 01:40 PM
Krashed, thanks for the info/picture, I thought the bracket bolt was holding the pump to the block and therefore had to remove the pulley to get at it. I thought that was a stupid design and it would've been if that in fact was the way to disassemble the pump from the motor. I went out and loosened the bolt you pointed at and the pump started to move so that is the only bolt that I have to remove.

You have given me "Hope" that I can get this done, it looks as though with the pump, the belt tensioner, idler pulley, and torque mount bracket out of the way, it's possible to loosent he timing chain cover. It also looks like there's enough room to get a finger inbetween the cover and block to release the lever for the chain tensioner.

I got an estimate yesterday to finish up from where I'm at and of course the garage said they would have to pull the motor even though I told them what I just mentioned above, their estimate was $1150-$1200.

You are correct about lofter the tapping because of to much valve lash, my question if not clear was, what is causing the "to much lash condition"? After looking at the lifter a little closer, I see where the nipple which is recessed and comes out the bottom, rotates. These are hydraulic lifters and the lash which is determined when the parts are manufactured and assembled is corrected or made up by the hydraulics within the lifter. You know how the plunger extracts from the chain tensioner, the lifter acts in a similar way, when it's pressurised, the plunger makes up the difference so there is effectively zero lash and your valve train is quiet. Another question of mine was how much lash can the lifter make up before it starts to tap, the plunger is allowed to only move so far.

What I did notice on the lifter I removed which I believe was the "tapper", the nipple on the bottom rotates but it takes a lot of force to make it rotate where as the new lifter rotates a lot easier. My guess is that the tapping lifter lost it's ability to make up the lash and that's why it started to tap. On the other hand, the parts could've just worn to the point where there is just to much lash for the lifter to make up the difference. Are you following me, does my explanation make sense? My bad lifter probably has some foreign material inside that has made it unable to function correctly.

Thanks for the pics and the support, I'll update you later today, believe I have enough determination to get at it for a bit.


07-10-09, 02:39 PM
No need to pull/drop the engine.

Unbolting the front cover and pulling it away form the block may give you enough room to push the lever and depress the tensioner plunger. Someone here said that will work. IF NOT, you can still drop that side of the cradle down a little and unbolt and remove the crankshaft pulley - then you will be able to completely remove the timing case cover and have full access to everything.

07-10-09, 02:49 PM
tateos, thanks for the reinforcement, I'm going to get at it shortly, if I can just get the cam back in position today, I'll be happy. I'm thinking that when I get the cam back into position and check the timing, I'll probably pull the front cover again so I can get a look at all of the cams and their positions at the same time. If one side of the motor is aligned and the marks on the gears are 90 deg in relation to the top of the cylinder head, should the other side also be aligned so that the marks are 90 deg in relation to the cylinder head? Obvioulsy, if the balancer is still on and I can get at the tensioner byreaching in behind the cover, I'm not going to be able to see the timing marks on the primary gears.

I'm 99% sure that I didn't move any of the chains in relation to the gears but I'm not going through all this work without checking to be sure.

07-10-09, 05:33 PM
Tateos is offline, but the crank gear and intermediate sprocket have marks which align at 12:00 and 6:00 when the 4 cam gear marks are at 12:00 relative to each cam cover seal surface. IF the timing is off, it takes (don't quote me) 17 engine revolutions to get everything back in the proper position, so if 1 cam has slipped a tooth, it will be off a tad in relation to the other 3.

07-10-09, 07:17 PM

07-10-09, 07:20 PM
If the tensioner is extended, you will not be able to re-install the cam

07-10-09, 09:00 PM
Thanks Submariner, I am hopeful that I'll be checking the alignment maybe tomorrow, I still have to remove the balancer so I can get at the chain tensioners. I was able to loosen the cover although there is a bolt located bottom center which is behind the balancer. I was able to loosen it enough to pull the timing chain cover back on the top about 3/4"-1" which allowed me to shine a light and hook and the lever on the tensioner, the lever on back side tensioner looks to be in a horizontal position. I hooked the hole end which is on the left or 9 o'clock position and I tired to pull it up but it wouldn't budge, pretty strong wire was used. I then was able to lay the blade of screwdriver on it and push down, it wouldn't move.

I've removed all the inner panels and everything that's in the way so it won't be that much work to remove the balancer so i canget at everything and get it done right. I guess the balancer bolt is torqued around 37-40 foot lbs, is that correct. I have no spark plugs in the engine, 2 cams out of service so I as wondering, do you think an impact will remove the balancer bolt withouthaving to hold the engine from turing with a lot of force. Am I going to have to hunt downt he flywheel to hold the engine from turning. By the way, does anyone know the size of that balancer bolt, looks to be around 20mm maybe 22mm?

Almost there........1 balancer bolt and 1 balancer to remove!

Why couldn't I move the tension release lever??

07-10-09, 09:04 PM
tateos, thanks for the comment about installing the cam, you may have misunderstood my last comments about getting after it and aligning the cams. The alignment was to take place after I got into the timing cover and released the tensioner so that I could get the cam back into position.

Now all I have left is to remove the balancer bolt and balancer. If someone got behind that cover without removing the balancer that was one skinny dude with some awful long fingers, would've been a hell of a pick pocket I'm sure!!

07-10-09, 11:16 PM
Does anyone know what size the balancer bolt is, the reason I'm asking is because I'm going to have to purchase a socket? Also, does anyone believe an impact driver will remove the bolt without having to hold the engine from turning or at least not having to get a real good hold on the engine?

Thanks to all who have commented and helped in any way...

07-11-09, 03:43 AM
Looks to me like it's a 21 or 22mm bolt head, a 15/16ths is real, real close. I must've read 30 different threads related to this bolt so I don't expect to much trouble getting it out. I probably built at least 50 motors back in the day and still have all the sockets that I needed for the same bolt back then, late 60's into the early 90's and none of those sockets will work, doesn't surprise me!

Hope to have a good look at the tensioners later in the day, with a little luck, I'll be putting things back together shortly thereafter.

07-11-09, 06:57 AM
The balancer bolt supplies the clamping force needed to drive the oil pump, which wraps around the crank snout. There is a very specific procedure used to re-torque the balancer, and it must be followed or you will have no oil pressure. You torque to one figure then tighten the bolt a certain number of degrees in 2 passes. (Anyone have the pre-2000 spec ????)

Either the starter motor needs to be removed in order to lock the flexplate from up there, or there's a plate under the torque converter which exposes the flexplate lower portion. You may be able to lock it from there.

07-11-09, 03:02 PM
Submariner, what I come up with for the crankshaft bolt is 37 ft lbs for the first pass and then an additional 120 deg.

I haven't removed it yet, I need to go purchase a socket, just don't know the size to purchase. I know I can buy a set but I'll never ever use a set of larger sockets like that again so I may as well just buy one.

Doc, correct me if I'm wrong about those torque specs.

07-11-09, 04:31 PM
I was able to get mine off with an impact without the engine turning, putting it back on and being able to hold the engine to get the 120 degrees was a real pita. Fortunately I was able to stick a bolt through the starter opening in the valley and lock the flex plate in place. You want to make sure you get that bolt torqued properly when putting it back together otherwise you will have oil pressure issues.

07-11-09, 04:39 PM
Thanks, Jeffrsmith, I was just leaving to get an impact because I just don't see how an impact could not loosen a bolt that's only torqued to 37 ft. lbs pus the additional 120 degrees.

I may have to hold the flex plate a little but it should come off without a problem. I bought a 23mm which was to small, went back and purchased a 24mm which is thew correct size.

Thanks for the comment....

07-11-09, 05:00 PM
The total torque works out to over 160 ft/lb., and with the fine threads involved, that's a lot of clamping pressure.

The impact wrench will remove the damper bolt, but the install should be done by the book.

07-11-09, 06:45 PM
How are you going to hold the flex-plate? There is a dirt cover/bracket on the bottom of the tranny that will be easier to remove than the intake manifold. With it off, you can get at the flex-plate with a pry-bar or something to keep it from moving.

07-11-09, 07:50 PM
There's a high-priced toothed tool which bolts in place of the starter motor. BUT, others have locked the flexplate with screwdrivers and bolts. No reason why it wouldn't work from the lower inspection cover either.

07-12-09, 01:30 AM
I was hoping the impact driver would lossen the bolt but it didn't. I really didn't want to crawl underneath the car to get at the flywheel to hold the motor from turning, besides, I don't have anyone to help me so I have to hold the motor from turning myself to remove the bolt, that's why I was hoping the impact driver would work. I believe it started to move the bolt just a bit but the longer I kept at with the impact just singing along, the socket and bolt started to get hot. I believe as the bolt got hotter, it of course also got tighter. I let it cool for a bit and tried again, same result.

Oh well, under the car I go, i'll figure a way to lock the flywheel from underneath and then use a breaker bar and an extension on it if I have to.

I rented the impact otherwise I would've let the bolt cool for a longer period and repeated that until i got the bolt loose.

At this point, once I get the timing cover off, I might as well do the headgaskets, everything is off that needs to come off other than the heads, :bonkers: lolol!!

When I was young, I would've had this done in a day or two, that's the way I was, now, if it takes awhile, then so be it. It's so hot, I turn a few bolts and then go inside for awhile and cool down, the car isn't going anywhere so it'll be there the next day waiting, that's the attitude that I have now along with a little more patience.........

07-13-09, 12:02 AM
That is one tough bolt, either that or it's just the fact that I'm getting older & weaker, as tough as it is, it's off :gungrin:!!

All I need now is a puller and I'll be able to get at the chain tensioners. Once I get the timing chains straightened out I'll be well on my way getting the motor back together. Going back together is always a lot easier and gratifying, at least for myself.

Progress, slow but sure....

07-13-09, 12:13 AM
Note: I held the motor in place from underneath, a couple of bolts and you have access the flexplate. I've taken enough stuff apart and didn't want to remove the intake manifold, it was simple enough from underneath!

I'm a bit surprised that some people have used the starter to loosen that bolt. I know a starter is pretty strong and is geared way up but it just seems like it wouldn't loosen that bolt. I wouldn't even try it for fear of breaking the starter hub or flexplate when the starter drive slams into the flexplate. The way it was explained, locking the breaker bar into position and then turning the starter, you know that starter drive is going to hit that flexplate pretty hard because the flexplate isn't going to move unless that bolt comes loose. I believe most would recommend against trying to use the starter to loosen the harmonic balancer bolt!

07-13-09, 03:22 AM
Krashed, did you use a 3 armed puller for the balancer or a two, I can't tell by the picture. I'm sure it's best to use a 3 armed puller but I may not be able to get a 3 armed puller on the balancer with the engine in the car.

Anyone can comment, all comments appreciated!

07-13-09, 03:59 AM
Krashed, if I would've looked a little closer at my own balancer I would've noticed that a 3 jaw puller is probably the only one that will work. I say probably because some people can get anything to work for almost any imaginable mechanical problem.

07-13-09, 01:05 PM
I was able to get mine off with an impact without the engine turning, putting it back on and being able to hold the engine to get the 120 degrees was a real pita. Fortunately I was able to stick a bolt through the starter opening in the valley and lock the flex plate in place. You want to make sure you get that bolt torqued properly when putting it back together otherwise you will have oil pressure issues.

Hey Jeff - I think that putting a bolt through the starter opening was my idea - glad to read that it helped!

07-13-09, 05:40 PM
That's a 3 jaw puller with a wide centering device on the tip of the screw. If it's not the same puller outlined in the FSM to use, it's really close!


07-13-09, 06:25 PM
That's the one. I suggest a good one - I pretty much totaled a Harbor Freight 3 jaw puller getting my balancer/pulley off. It was amazing to me how easy it was to re-install it and re-tighten the bolt!

07-13-09, 06:54 PM
Getting the balancer bolt out was a bit tough, took every bit of my 200 lbs. to get it loose. The balancer was nothing, mine came right off with not a lot of resistance. I now see how the tensioner works, at least the tensioners on my motor. Knowing now how they work, with the timing cover loose and pulled out at the top, I possibly could've released the tension on the back chain which would've allowed me to position the cam back into place, not sure about the front one though, it would've been tough.

With that being siad, if you remove everything to loosen the timing cover, you may as well remove the balancer bolt and balancer to give you complete access to the timing chains and tensioners. You can make sure the chain tension is correct and also check the alignment of all the timing chains and gears. Even though I'm sure I didn't move the cams in relation to the sprockets when I replaced a lifter on the front bank, and ran the car afterwards, I'm still going to remove the front cover and check all the cams with the timing cover off just to be sure of the alignment.

I believe you could have one of the cams off one tooth and probably not know it when you started the car, unless of course a valve hit a piston. There's probably ample piston to valve clearance so if you were off one tooth, you would'nt damage/bend a valve. I would guess that the car would still run pretty good and if you susoected a miss, you would probably think it was a spark plug or wire. To be sure, I'm going to have a look, will take a few extra minutes but I'll have peace of mind knowing everything that was done, was done correctly!

I'll probably have most of it together tonight, if I'm into it, I may finish, it will be running soon.

Thanks for the help and support!

07-13-09, 06:57 PM
Krashed, the puller I used looked identical to the one you showed in the picture, fit perfectly. Thanks for the pics, I know it takes time to get on the computer, locate different pictures and then paste them in, I appreciate yourself amongst others who take their time to help others that they don't even know:thumbsup:!

07-13-09, 08:10 PM
Hey Jeff - I think that putting a bolt through the starter opening was my idea - glad to read that it helped!

Your right Richard, that bit of info you provided saved me a lot. I was agonizing over how I was going to fabricate something similar to the factory tool to hold the flex plate.

07-13-09, 08:25 PM
rodman, The Northstar is an "interference" engine. A severely out-of-time cam will destroy the engine because the valves will hit the pistons. I doubt that 1 tooth off would do that, though, but it would definitely change the overlap timing on the affected bank.

07-14-09, 01:01 AM
Made a lot of progress today although I ran into a problem that I was going to note when I finished this job, the problem being the soft material that the cam cap bolts are made out of, I believe some sort of aluminum alloy. When I did the first bank I rounded off a corner or two on two cam cap bolts and had to use an impact to get them out afterwards. I was lucky because they were in the front and there was room for an impact, I was much more careful on the back bank because of what I experienced on the front bank! I've used tools most of my life so I was a bit surprised that I rounded a corner on one of those bolts to begin with. My suggestion is to use a good 10mm impact socket and make absolutely sure your good and square with the bolt, the slightest angle with that socket and it'll slip because of the tapered head on these bolts.

To relieve the tension I had to move the cams so there is virtually no tension from either direction on the chain tensioner, then you can release the lockiing lever otherwise, with the slightest bit of tension from either direction and you can't move the locking or release lever on the tensioner. Once released, the rest is quite easy, position the cam, then I would collapse the tensioner, move the cams up and back just a little bit, .125", and then release the tensioner which you can here the ratchet or detent catch as the tensioner creates tension on the chain. I virtually found what I would call a zero position with an equal amount of tension, virtually none to speak of, on either side of the tensioner, then I let it ratchet out.

I did that several times and once everything is settled into place, there is about .25-.375" slack in the chain inbetween the two cam gears while applying pressure up or down on the chain, that feels quite normal to myself. It's a good thing I decided to go back over the fornt bank because if ya'll remember, I kept saying that the chain was real tight when I clamped the cam back down. It was real tight, way to tight when I took that cover back off, may have gone on without a problem and then again, it could've broken a cam or wiped out the front bearing boss and cap from to much tension pulling down on the cam.

There was a reason that the first lifter I changed didn't fix the problem, it was devine intervention which made me go to he back bank and then check the front again which displayed that overly tight chain.

Back to the cam bolts, when I got the back bank exhaust cam back into position, I was tightening down the number 3 cap with one hand and a 3/8's ratchet while I was holding the tensioner in with my other hand. I was hardly turing one of the bolts when I felt the ratchet all of a sudden get real easy, I knew the socket didn't slip and my stomach turned like when you see someone in the dark that shouldn't be there. Sure enough, my worst nightmare, I broke the bolt off and when I looked, sure enough, the top of it is about 3/8-1/2' down in the hole. To make matters worse, it's the exhaust cam which is the closest to the firewall. I looked and it didn't look like there was quite enough room for a conventional drill, turns out, there was just enough room. Before attempting to remove the threaded part of the bolt, I took the other piece and tried to drill it while clamped in a vice. It drilled pretty easy and looked like it was aluminum so I stuffed a bunch of rags around that boss and got after it attempting to drill a small hole for an easy out. I knew the bolt hadn't bottomed out because the cap still had about 1/4' to go so my thinking was that the bolt should turn real easy if can get just a little grip on it. I was lucky and drilled a hole dead center and without much effort or force, an easy out turned it right out using pretty much just my fingers.

I was going to leave that for tomorrow but I thought I wouldn't be able to sleep so I fugured I wanted to know my destiny prior to going to bed tonight. If I couldn't get it out, I'm sure everyone knows the consequences, remove engine, machine shop, and on and on........

I put everything back together other than that 1 cap, in the morning I'll get a bolt and should be able to finish up, more devine intervention near the end of the day helping me with that bolt!





07-14-09, 01:04 AM
I think the second picture from my previos post shows best the hole I drilled in the bolt, my camera isn't that good with close ups!

07-14-09, 01:07 AM
Submariner, when you stated that one tooth off would probabaly not bend valves but would change the overlap on the cam is precisely what I was thinking and I can see where that could happen real easy if someone was in a hurry and didn't complete all the checks required. It's possible with a cam a tooth off, you might notice a difference a full throttle, enough to raise your eyebrows and then again maybe not. Better be sure knowing that you won't bend any valves and that you'll have full power!

07-14-09, 03:21 AM
I thought I would show another picture with the easy out I used when I first removed the broken bolt, nothing to brag about, breaking a bolt, but getting it out without damage to the hole or threads is! How in the world I broke this bolt is beyond me. Now, I'm afraid to torque the others for fear of breaking another. I know I wasn't applying more than 5-10 ft lbs pressure when tightening that bolt. Now that I think about it, when I broke the bolts loose, It felt like I may have cracked or twisted one then.

I believe all of the hard work has been done and now it's just a matter of bolting on all of the external parts. My only concern at this point is the back cam cover, it was difficult to remove, maybe it'll go back on a lot easier than it came off. Sometimes it does work out that way, you struggle to remove a part and when you go to install it, it just about falls into place.


07-14-09, 02:52 PM
Yeah, I've heard about those bolts being fairly weak. I'm glad that you were able to get it out though! That method sure beats dropping the cradle and drilling! :p ...The back cam cover was not very hard to install for me; but then again, the engine was out. Are you still planning on doing the headgaskets?

Mark C
07-14-09, 04:00 PM
If your off a tooth the misfire shows up at idle and not at the higher rpms. Ask me how I know. I just reassembled my block on the ground a couple of weeks ago, complete with everything right down to the spark plug wire, only to stuff it back into the car and have an idle misfire. After ruling out all the easy stuff ( coils, plugs wires etc) I pulled the front valve cover, both those cams were timed properly. Pulled the back (after pulling fans and lowering the front of the cradle 6 inches) and the exhaust cam is retarded by one tooth. Had to look at it about 5 times before i was sure it was off, as you can barely see the timing mark on the cam gear with the shock tower right there. So triple check all you cam timings BEFORE you put the engine back together. Still have to put it all back together again.

07-14-09, 05:25 PM
Krashed, No, I was only kidding when I mentioned the headgaskets. If I had the motor out I would have them done, for now though, it's only the lifter that I'm replacing.

Even though I've read all about the headgaskets and failures on this site, I'm still a little old school on if it's worked for 100k miles, it'll probably work for another 100k miles. I used to associate with an old gear head, he built a lot of race motors, mostly small block Fords way back when. He was the kind of guy who had a family, not much extra money, so when it came to racing cars, he was on a very tight budget and did everything on his own. One day he was getting ready to build a new motor and I asked him where he got the block, it looked new so I assumed he bought a new block from Ford. He laughed and said he picked it up from a junkyard and that it was a high mileage motor that was still running well. I asked him why he would do that and he said, this block has been run for 100k miles, it's been heated, cooled down and flexed over and over who knows how many times. Any shifting of the core would've occured by now and if there wee any weak area's in the block, they would've showed up by now. He would certainly have it magnifluxed and alignbored but felt that he had a known good block and the chances of failure are much less than if he were to buy a new block which hasn't been subject to the stress and heat like a used block!

Those cam bolts, I'm afraid to tightent them, I can't remember the last time I've broken bolt. I had to use a broken drill bit with about 3/4"-1" sticking out the drill or I wouldn't have had enough room to get in there to drill it. It's really a very soft bolt, I took the half I had like I said and drilled it but beofer that, I took a hack saw and cut a little groove in the side to hard it was, it wasn't hard at all, actually quite soft. This gave me a bit of confidence that I would be able to drill and remove the broken part of the bolt which I did.

07-14-09, 05:37 PM
Mark C. Sorry to hear that you're having to redo some of your work. I know what you mean about looking at it several times because I did the same when I did the front banck. I aligned the cam marks so they were perpendicular to the top of the cylinder head. It's virtually impossible to look at the marks from a straight forward position so your alwqays looking from some sort of an angle. The marks are easily distorted because of th eangle and then you second guess yourself. I finally took a square and laid it on top of the head and aligned the "T" with the alignment marks on the cam and they were perfectly aligned. I felt a lot more confident when I used the square, looking from all the different angles realyy distorts the way the alignment marks look.

When you said that you ruled out the easy stuff first, it reminded me of what I said about a cam being 1 tooth off. Most people would figure they probably have a bad plug or wire, apparantly, that's what you thought or at least was hoping that's what it was.

Hope everything goes back together real easy for you, thanks for the insight!

07-14-09, 06:05 PM
Mark C. , it had to be the back bank didn't it. How are you going to move the cam gear one tooth? Are you going to remove the timing cover so you can get at the chain tensioner to remove the tension? Actually, I think there's enough slack in the chain that you could probably have someone hold the chain tight so the tensioner doesn't ratchet out one more click and while they hold the chain, loosen the cam cap bolts and tilt the cam enough so you can turn it 1 tooth.

You probably know this but you can position the exhaust cam where all of the valves are closed and there's no valve spring pressure ( very little ) on any of the cam lobes. I was able to do this on the front bank, I could turn all of the lifters by hand so I knew there was little to no spring pressure on the cam when I loosened the cam cap bolts.

Note: I've seen it mentioned that there is a tool available to hold the timing chains I guess, you may want to check that out.

I do know, if you tilt that cam and you hear that tensioner click, your chain will get to tight when bolt the cam back down.

Mark C
07-14-09, 06:53 PM
I have the tool set for holding the chains inplace, infact its out there in the driveway sitting on the chains now. Going to try and rotate the cam the one tooth tonight, then glue the rubber gasket back into the covers because they seem to strech a bit after the engine has been heated up a couple of times and won't stay in the groove in the cover, then I'll check them one more time for proper timing and put the covers back on tomorrow, then button everthing back up and I should be good to go.

07-14-09, 07:41 PM
Yeah, the valve cover gaskets usually have to be replaced because contact with oil causes them to expand. If you put it in the freezer it will shrink it a little, but you will have a limited window of time before it expands again.

07-14-09, 09:13 PM
MarkC. you mentioned not being able to see the alignment marks on the cam gears because of the strut tower. What I did for the back bank was turned the engine where I could get at the marks, then I took some white nail polish from my daughter and made a mark on the backside of the gear. I did that for both the exhaust and intake gears on the back bank. Then you can look from the drivers side of the car and get a nice straight look without having to deal with any illusions created by looking from a funny angle.

I judt got done rotating one of my cams and I had to loosen the cam from the head to get enough slack in the chain. With the tensioner collapsed all the way, there's just not quite enough slack to move the chain.

I'll be back shortly, need to step outside....for a minute.

Mark C
07-14-09, 10:27 PM
I went out and disconnected the exhaust cam gear, with the holding tool inplace, and slid the gear off the cam and immediately heard a click and thought one of the tensioners had extended. Boy was I pissed, cuase theres no way to get at the tensioners on the right head with the engine in the car. Turned out it was just the cam snapping back to a neutral position. Went about rotating the gear one link, so I thought. Its really hard to rotate the right bank exhaust gear one link counter clockwise (from the fender side) while trying not to drop the gear down into the engine. Put it back together and come to find its still in exactly the same position as when I started. Got to dark to try it a second time. Try again tomorrow.

07-14-09, 10:46 PM
Mark, sorry to hear your having a problem and I understand about trying to hold something while using your other hand for another task. I did my front bank with the timing cover on the car and managed to get the job done but I know now that the tensioner had come out some and the chain was to tight when I finished. I thought the chain was to tight then but I know now for sure that it was to tight.

Somewhere along the line I took the timing cover off and does that make a difference, to be able to release the tension on the chains, of course you know that if you had the motor out and put the chains on with the tensioners collapsed.

Good luck, go hit a couple of golf balls, release some tension, lol!

07-14-09, 11:01 PM
Here's where I'm at, I alogned all the cams to make sure everythign was okay. When I did that, the intake cam on the rear bank was off about 3-4 teeth, seemed like a lot and I was thinking maybe I don't have everything aligned. I do remember that when I did the back bank, I did the intake cam first, looking at the lifters that is. When I did that I wired the cam sprocket to the chain so it couldn't move. When I finished and went to the exhaust cam, I moved the wire to the exhaust cam when I should've just used another piece of wire and left the intake gear wired like it was. When I dipped the exhaust cam, I remember the chain sliding acorss the intake gear and I thought it may have moved a tooth or two at the most.

Okay, I aligned the gears on the front bank so the marks were perpendicular to the top of the head, they both lined up, when I looked at the bacl bank, the exhaust was lined straight up but the intake was off. I've since moved the intake cam so that all 4 sprockets have their marks pointing straight up or perpendicular to the cylinder head. I notice that the #! cylinder has all 4 valves closed and the exhaust lobes are coming around so that cylinder is firing. That should mean I'm close to if not on TDC, is that correct. I'm pretty sure I'm ready to button it up although when I looked down by the timing chains and oil pump area, ( I was looking for timing marks on the crank sprocket ) I noticed that the piston for the small chain in the back, was fully extended. The piston also had the brown color form the oil for about the first 3/8" and then the last maybe 1/2-5/8" looks clean and shiny like it just protruded recently.

if you remember, my other thread, I've been looking for a whining noise which I thought could be timing chain related because it kind of sounds like a chain rubbing across some other metal. I can't see the tensioner real good without removing the oil pump but I feel like I need to do that. Why would that tensioner go from 3/8" to about 1" all in 1 move which is what it appears it did by looking at the discoloration of the plunger. The only way it could mive that far at once, I think, is if the plastic/nylon pad on the tensioner broke loose and now the chain would be riding on the metal backing plate or shoe where the nylon/plastic is usually sittiing. That would explain my whine, chain rubbing against aluminum I guess.

Does anyone have a picture of what that tensioner should look like? Is it a big deal to remove the oil pump? I wouldn't think so but I'm not afraid to ask about something that I'm not sure of.

I may have gotten lucky and found my whine at the same time as fixing this tapping noise!!

07-14-09, 11:50 PM
I also found this to be quite strange when I was down looking around inside the timing chain area. I though as long as I'm down here, I'll clean the end of the crank, make sure the key is clean and fits in the groove correctly. There is no keyway, the inside of the balancer is like looking in a pipe, there is no groove, no keys, looks as though it doesn't matter how you put it on. I couldn't find anything that looks like a timing mark so I guess it goes on anyway you like, is that true or am I missing something?

07-15-09, 01:03 AM
I looked back and the pictures where krashed provided a link, page 2 of this thread, show's the inside tensioner pretty clearly. Looking at his, the chain is nowhere near the plunger from the tensioner, mine it appears as though the chain is almost touching the chain, may even be touching the chain. My lunger is extended like I said earlier, maybe 1 " when Krashed tensioner looks like the plunger is out about 3/8" which mine shows the brown area to about 3/8".

I'm pretty sure my inside chain tensioner has the plastic broken or worn off, I"ll have to remove the oil pump to get a good look. I guess I may not have to remove the gear and or chain to change the tensioner, does anyone know the answer to this, will I have to remove the chain and or sprocket?

If I'm right and I believe I am, I more than likely found my whine, looks as though the chain has worn through the plastic allowing it to rub on the aluminum backingplate causing a whine, then rubbed through the aluminum backing plate and may now be rubbing on the plunger! Wow, this has to be the whine I've been hearing. I'll know more as soon as I get the oil pump off, I just went out ans looked and am quite sure the tensioner isn't all there.

Maybe these pictures will help to show what I'm talking about.




07-15-09, 09:17 AM
IF the chain has been rubbing on the plunger end as opposed to the nylon slipper, I would replace the chain as a matter of insurance. If one slipper is worn, they all are. Replace all slipper and tensioner faces. I believe the oil pump unbolts and slides off the crank snout. Tateos will know for sure.

The crank pulley/balancer is a friction fit with the bolt torque as the locking mechanism. It serves no timing or crank reference function, so no marks. All the engine timing is referenced to the rear exhaust cam peg, sensor, and the crankshaft reluctor wheel and two crank timing sensors. No way to mechanically fool with timing.

07-15-09, 01:43 PM
Submariner, thanks for the info, not sure what you could see with the pictures because it's hard to get up in there with a camera. I'll be taking the oil pump off later today when it cools down a bit, then I'll be able to get a good look at it. Your probably right about 1 slipper being worn meaning the others are also worn out. From what I can see, all of the others look good/normal while that one looks like it may have broken.

The dealership I just called told me that part is not available, can't order it, nada! I have a hard time believing that the shoes , as they call them, are not available nor is the tensioner available. I asked about ordering and they said GM does not have those parts available.

I can see I'll be making plenty of calls today.

07-15-09, 03:01 PM
Submariner, this is a picture of the tensioner and how badly worn it is.



Because most of it sits behind the oil pump and the angle that you have to view it with the engine in the car, you could easily miss this. What kind of tipped me was the discoloration on the plunger, see the second picture. Most of the internal parts that I'm seeing have that bronze look from the oil, the plunger had that bronze look like I mentioned a few posts back for about 3/8" and then there is this dramatic change of over 1/2" of clean shiny plunger. Each detent probably allows the plunger to move out maybe 1/8" at most would be my guess.

I was also looking for the timing marks to be sure I had the cams positioned correctly, that also got me down in there more than I wanted to be.

Now that the oil pump and tensioner are off, I can see the timing marks which would be lined up if not for the tensioner unable to make up the difference ( slack in chain ). The crankshaft mark is about 1/2 tooth off from being aligned with the ( idler gear I guess ). his tells me that the cams were several dgrees out in relation to the crankshaft. I know the computer cam make up for electronic differences but the cam timing was many degrees off. I thought the old girl was getting a bit sluggish, being a betting man like I am, I would suspect a lot of pep being restored when I finish. I would guess by looking that the cams were about 6-8 maybe 10 degrees retarded in relation to the crankshaft. Without stoppingto think about it, I'm pretty sure they would be retarded.

I'll update you later....

07-15-09, 03:46 PM
I believe I've found the grinding/whining noise from the other thread that I started. At first it was a grinding noise, then it went away for a bit and then it started whining, that's what I describing in the other post. It all makes sense now, when it wore through the nylon, the chain was rubbing on a thin plate of what appears to be aluminum, thus the grinding noise. Once the chain wore throught the aluminum plate, it started to rub on the plunger which is a harder metal thus a different noise, the whining. At that point it wasn't as pronounced and that was because teh tensioner was at full extension and therefore didn't have as much tension on the chain, less tension, not as much noise.

I'm really happy now because I was starting to think maybe it was a torque converter or some other trans related problem even though the noise seemed to come from the front of the motor.

On the down side, I've checked everywhere and the soonest I can get a tensioner is 2 days, not bad I guess!

07-15-09, 03:56 PM
Jake may be able to help you with some spare parts like tensioners, chains, guides.

I never removed my oil pump when I did my HG project - it was not in my way and there was no reason to disturb it.

07-15-09, 04:29 PM
I believe the sequence is to align the crank and intermediate timing marks with cylinder 1 at TDC compression and then align the cams and chains with the special cam locking tool before you pull the tensioner retaining pins. The crankshaft keyway (sprocket key) will be at 1 o'clock, looking straight in. Use cam assembly lube in the bore and tighten the intermediate sprocket bolt to 44 ft/lb.

If you rotate the engine even once the crank and intermediate sprockets look out of time. I think it takes 17 revolutions to get back to where the marks are perfect IF you don't pull the gears and manually align the intermediate.

07-15-09, 04:56 PM
Thanks Submariner, I just went out and looked, the keyway is in the 1 o'clock position so I'm ready to go as soon as I get a new tensioner. Yesterday I had aligned the cams, looked at the lobes for #1 and could see it was at TDC. It was when I looked down in the timing chain area, looking for the timing marks on the gears for confirmation that I was at TDC, that I found or saw that bad tensioner. Since I removed the oil pump this mornig, I mentioned that the alignment marks were virtually right on except that the crank gear mark was about 1/2 tooth off, that because of the slack in the chain. I bumped the motor maybe an 1/8th of an inch and everything is aligned so I'm good to go.

I guess I can put some of the parts back together, actually I could put everything back together except the front of the motor, timing cover, power steering pump and so on. Now I'm pretty excited and can't wait to hear the engine run again, I know it'll be nice and quiet without that annoying whining!

Thanks again for all the help, I will be in touch.......

07-15-09, 08:06 PM
Wait a minute. It sounds like you are saying the chain rides on the tensioner. Does my memory fail me, or does the chain not ride on the chain guide, which pivots from the top, and the tensioner piston presses against the guide to provide tension?

Maybe I misunderstood?

07-16-09, 12:18 AM
tateos, in the first pictire that I've attached, it's a bit blurry but I believe you can clearly see the chain sitting down inside of the chain guide which is attached to the end of the plunger from the tensioner. The chain shouldn't be sitting down inside of the guide, the guide, If i'm not mistaken should be pretty flush all the way across. There may be a small lip on either side, maybe 1/8"-1/4" to keep the chain aligned although it wouldn't surprise me if it was flat all the way across. I don't know because mine has worn through the guide and the plate that the guide sits on until finally it has met up with the plunger from the tensioner which you can clearly see in the second picture. In that second picture, the nylon guide which is attached to the end of the plunger should be flat all the way across, from a top view it should look like a flat piece of nylon/plastic, frm the side there is a curve to the guide.

Not sure what your asking but I hope that this is a little clearer, if I had a new tensioner to compare pictures you would see what I mean. Mine is thoroughly trashed, there is no guide left on the end of the tensioner plunger.



07-16-09, 12:27 AM
This picture that Submariner attached may show better what I'm trying to tell you. As you can see, the lower tensioner which keeps tension on the interior chain is pictured quite clearly. As you can see the chain is riding on top of the nylon slider which is attached to the end of the tensioner plunger, mine was worn through so far that the chain was up against the plunger/psiton. On my car, most of the guide attached to the end of the plunger is sitting behind the oil pump and you can't see it, you can only see the tensioner.

Attached Thumbnails
http://www.cadillacforums.com/forums/attachments/northstar-performance-technical-discussion/51286d1247690008t-lifter-starting-tap-needs-replacing-crank-sprocket-timing-marks.gif (http://www.cadillacforums.com/forums/attachments/northstar-performance-technical-discussion/51286d1247690008-lifter-starting-tap-needs-replacing-crank-sprocket-timing-marks.gif)

07-16-09, 12:45 AM
In this picture which is my tensioner still installed with most of the guide behind the oil pump. If you enlarge the picture, the red line is about where the top of the guide is, that's where the chain should reading, on top of that guide. The blue line obviously shows the bottom of the chain which is riding down inside of the guide and up against the plunger.


07-16-09, 02:07 PM
I have been enjoying your thread. Sorry - thanks for trying, but I can't make out anything in your pictures - too blurry for me, plus it's been over a year since I was looking in there. Anyway, I'm glad, as you are, that you took off the timing case cover to fix this thing the right way. You can be proud of yourself when it's all over.

07-16-09, 03:20 PM
Wow, that is one worn chain guide.... It might be a good idea to replace the chain itself as well as the guides. With it riding on metal like that there's no telling how may scratches or burrs are on the chain. Without replacing the chain, you might be attaching new guides to a sort of belt sander.

07-16-09, 04:15 PM
I'm anxiuos to see the new tensioner and especially the chain guide part of it. I believe the guide plate where the chain rides is not solid nylon/plastic all the way down to the plunger or extender. My guess is that it's about 1/4" thick plastic/nylon that sits on an aluminum plate like a bridge on top of the extender. once you wear through that plastic/nylon there's not much aluminum to go through, just a fraction of an inch. At that point, if it wears that far, the bridge collapses and the chain falls down on top of the extender, that's why I saw the 1/2-3/4" of clean exrtender. The chain wore through and then the extender popped out to try and make up the difference. I can see on all of the extenders that they come out right 1/16" for each detent, I thought it was about 1/8" but it's more like 1/16th.

When I saw that 1/2-3/4" of shiny extender I suspected soem thing was wrong. To be honest, I sort of had forgotten about the whine because I've been focussing on the lifter. In the back of my mind I was still looking at things that could've caused a whine but had no intention of removing the timing cover even though that is where I originally thought the whining was coming from. Now that I know what it takes, I believe anyone could go into the timing cover area and have it apart, fixed abd back together in 2 hours, 3 at the most. There really is not much to remove, now it may be more time consuming to change some of the other sliders or tensioners and you may even have to remove a cam cover for something but the lower tensioner could be changed rather easily.

Krashed, your comments about the chain are well taken, Suubmariner had mentioned virtually the same.

I should be up and running tomorrow, hoping that I've cured the tapping. I wish I had a micrometer because I would like to measure the exhaust lobe(s) on that #8 cylinder and compare them to others. Actually I'm sure someone here knows what that lobe should measure. That would tell me for sure if I've cured the problem or not. Like I said many posts ago, the new lifter, I think, will make up about .004's as compared to the old lifter. If the tap is a combination of the lobe being worn .004 and the lifter being worn .004 to add up to .008's wear, then by addding .004 back in should resolve the tap, I hope!

07-18-09, 01:10 AM
Made some progress today, lower chain tensioner back in place and then I decided to put the back cam cover back in place. Like I've said, I expect that would be the biggest problem going back together but that also sometimes even though something comes apart hard, they fall back in place quite easily. That back cover was so hard to get off, I knocked off 3 of the sparkplug seals from the inside of the cover, also the cover gasket itself was pulled from the cover in various area's when I finally oulled it loose. I didn't want to have any of the seals fall off or come loose while trying to replace the cover so I used a small bit of silicone in the corners of the cover gasket and a few little spots on the inside of the sparkplug seals. I believe there is just enough room to get a couple of fingers under the cover once it's in place, to check the seals and insure they're where they should be and maybe somehow get them back in place if they did fall out. That explanation is the reason that I "tacked" the seals in place, to avoid checking them in the blind and then , even worse, have a good sized oil leak.

I put that cover in place, moved that big bundle of wires that runs across the back out of the way and the cover just dropped right into place, how nice. I was being bothered quite a bit so that's as far as I got but there really isn'tmuch more to do. Replace the timing cover, balancer, belt tensioner, idler pulley and power steering pump in the front of the motor. Then the front cover, a fan and the radiator support. Put the plugs in, connect the wires and away I go!!

Did I fix the tap, not sure but I would give it a 70% chance that I fixed the problem. The whine I know will be gone, how nice that will be although, with the a/c on or the radio playing, you couldn't hear the whine. Everything had to be off to hear the whine so it's not like it was a head turner while you drove down the road, just annoying knowing that it's there and something is causing it.

Here is a picture of the old and new tensioner, also I mentioned a few posts back about marking the cam gears on the back so you can check the alignment from the backside. By looking from the backside, you have a much beter view of the alignment versus trying to see the marks from the front which is virtually impossible with the strut tower in the way. I added 1 picture which shows the old tensioner still bolted in place, you can see the bronze and shiny area on the plunger which got me curious to look closer.






I've been having a hard time posting, not sure if it's my computer or the website, seems as though it may be the website.

07-18-09, 02:25 AM
Here are some better pictures of the tensioners, the previous post showed a top view only. In these you can see they designed the replacement a little differently with more support in the center of the pad!




07-18-09, 10:49 AM
That was really worn bad - I'm surprised that you didn't jump timing. The old tensioner certainly could not have been providing much tension.

07-18-09, 11:57 AM
jeffrsmith, I thought the same when I saw it like that, especially when I removed the oil pump where you can get a good luck of whats going on. When I removed the tensioner I tried to pull the chain to see if I caould move it a link but I couldn't. There is a slider on the opposite side, as long as it's not broken, it appears to take up just enough slack so that the chain cannot move a tooth. That slider creates a slight a curve in the chain between the two gears which keeps the chain short enough so that dreaded experience does not occur!

The way the the slider on the original tesnioner is built, once the chain wears through the pad and backing plate which is about 1/8-14" thick, the chain will drop all at once, maybe 1/2" all the way to the extender.

I recall drving on the highway one day and all of a sudden there was a big jerk, like the engine stopped for a split second and started back up, it was like a jolt, don't really know how to explain it. It very well could've been when the chain broke through the tensioner pad and the timing would've been thrown way off for a split second. I never did associate the grinding noise or whining with that jerk way back when but it wouldn't surprise me if that jerk was a side effect of the pad breaking/wearing.

Have a good day, I'm enjoying the British open right now with ole Tom Watson leading the tournament! I'm going to put my car together when they finish, shouldn't take long at all.

07-18-09, 11:02 PM
Well, I pretty much put everything back together today with the exception of the balancer because I don't have the ability to tighten it myself. Tomorrow I'll have some help to tighten the balancer and should be up and running shorty thereafter.

That car is so ready to run I could start it without putting the plug wires back on and it'll probably run. I'll know shortly if the lifter I replaced will cure the tapping problem, I hope so. It would've been a lot of work for nothing if the tapping is still there, another option would've been to replace all the cams and lifters.


07-20-09, 12:29 AM
I finished up earlier this afternoon, everything went together as good as can be expected, really went back together quite easily! I started the motor and it sounded just fine for a couple of minutes, then it started tapping again. I kept the rev's up over 2k for those 2 minutes, closer to 2500 RPM's. Of course I was disappointed but also curious why the motor strill has a tap and whar's causing it.

On the brighter side, my whine is gone.............!!! Finally, what started out as a grinding noise eventually turning into a whining noise, has been fixed. There was no doubt in my mind after seeing the timing chain tensioner gone bad, that it was the cause of the whine.

Back to the tap, what is causing this tapping? I let the motor sit for a couple of hours, started it again and it was quiet for about a minute before it started to tap. If I rev it up to 2500-3000 RPM's you can hear it tap, barely, but you can just make it out through the engine noise from being revved so high. When I let it drop back to idle, the tapping goes away for a few moments before it returns. As the tap returns, it's quieter at first and becomes more audible in the first half minute until it reaches a point where it's pretty noticeable. What I'm trying to say is that the tapping changes depending on the conditions or what is going on.

It almost seems as though the lifters near the back of the motor are starving for oil or at least the lifters at the back for one of the cams. When I was und er the covers, everything seemed to be coated with oil but I could've missed something, I wasn't looking for an oil starvation problem. When I let the motor sit for a bit, it's quiet at first and when I rev it pretty high and then let the RPM's drop down to idle, it's quiet for a short time before the tapping comes back. If an oil passage was partially blocked, I could see where letting it sit for a bit would allow the oil to get through the partial blockage and lubricate parts near the blockage.

The tapping started after the grinding and whining noise, several weeks if not a month or two after the whining noise. Where did the material go that broke off the tensioner slider and the backing plate for the slider. There was probably some pretty good size pieces that broke off the tensioner. When I had the cover off I was wondering where would the pieces and or particles go from the tensioner. I looked around inside the timing chain area and there is a small floor or lip at the bottom of the block at the very front which looks like a ledge, as you follow that lip in towards the back of the motor, it only extends in maybe 1 or 2 inches from what I remember. If a part from the tensioner dropped, It could lay on that ledge but if it fell off the ledge, It would go to the bottom of the oil pan, at least that's my guess without having the oil pan off. The oil pump is right in the immediate area, not sure where the pick up is, probably pretty close to the pump, that being said, if particles fell fro the tensioner they probably were picked up by the oil pump and pumped through the engine. There could be some foreign material blocking an oil passage to a lifter or set of lifters!!

If I would've suspected something like that I would've prelubed the motor with the cam covers off and I would've been able to see how much oil was getting to all the lifters.

Not sure which way to go now, my body is not what it used to be. I can't roll around on the ground or reach over the motor any longer. I saw nothing under the cam covers that would cause a tap, the timing chain area is now all in good shape, that doesn't leave a whole lot of other possibilities!

I did find an engine shop last Friday that works and or exchanges Northstar motors, I may take my car there. They said they would rebuild my motor or exhnage it with another, whatever I wanted.

Any suggestions would be appreciated..........

Some of my grammar and spelling may be off but I'm having a hard time getting on this web site so I'm not changing the page until I hit submit for this post.

07-20-09, 08:25 PM
This is quite frustrating, I go out and start my car today for the first time, it taps fopr about 5 taps, a second or two, then it's quiet, like you drove it off the lot. I rev it several times, it's quiet as can be. I go okay, how long will it go untill starts to tap. I idle it pretty high, over 2k for about 2 minutes, let it idle down, it's quiet. A few seconds later and it starts to tap again. I let the car sit maybe 10 minutes, start it and it's perfectly quiet for maybe half a minute, then it starts to tap. I have never had a women, so tempermental in my entire life. She's done blown a gasket this time and feels like tapping her heels when she wants to, my oh my!

I'm really stumped although I believe the tap is from the valve train and may have something to do with an oiling problem.

07-20-09, 10:22 PM
yeah, it sounds like what you said. One of the passages probably has a small blood clot near a lifter. It's probably not a complete blockage otherwise it would tap all the time constantly. If you're lucky, maybe after a certain number of start-ups it will clear itself, but you cant be sure. Blood thinners are probably not a good idea for this patient either because then the heads will get no blood at all from it leaking out the main bearings. The veins are probably too small for a stint to be put in. I think the only option is more surgery, just taking the heads off and cleaning them. Studding the block would be good too... Maybe the best bet is to take a break from it for now at least until you regain your strength; maybe it will heal itself. If not then more surgery would be your best bet.

maybe I've been watching too much House.... lol

07-21-09, 01:00 AM
Krashed, I appreciate your comments and I believe your right about the patient. She probably has a blood clot somewhere and maybe it'll move and get flushed out or it may stick in a worse place and become terminal! You are right about needing a break, I'm going to let the old girl sit for a couple of days. I am going to start her a few times a day and see what happens, we both need a rest, me more than her lol.

I've never had this kind of a problem before, basically an intermittent mechanical problem. An intermittent electrical problem is not unusual but from what I've experienced an intermittent mechanical problem is unusual. If a part breaks, it shows up as a failure and won't work again correctly 5 minutes later.

I'm not in a hurry so that helps me keep my sanity about this problem so that's a positive. Another positive that I can take out of the work I did was finding that tensioner which was the cause of the whining that I was hearing. This may help others if they hear some unusual noise near the front of their motor, they will at least have something to go on other than speculation. I'm surprised that there wasn't anything related to that lower tensioner failing on this website. If you look at one of the pictures that you forwarded to myself, ( picture showing the inside of the timing chain compartment ) the upper tensioners for the cams has a long stretch of chain with little to no curve in the chain and not much of an angle where the chain first meets up with the tensioner/slider. The chain for the lower tensioner has a very short throw and a fairly large angle where the chain first meets up with the tensioner/slider. As the chain stretches and the tensioner extends, that angle increases to the point where it appears it wouldn't take much to saw through the slider.

I ran my motor up in the higher RPM range quite a bit so my chain may have stretched a little prematurely and that's why my tensioner failed with less than 110k miles on the engine. I say that because I read a lot of posts where people have a lot more miles than that on their cars and never no mention of a tensioner failure.

Like I said in a previous post, I'm starting to believe that there was a chain of events that have led to my tapping problem. I heard the grinding noise which I believe was the chain rubbing on the backing plate for the nylon/plastic slider after the chain had worn through the plastic/nylon. Once the chain ground through the backing plate which appears to be aluminum, it started rubbing on the end of the extender which is a lot harder metal and therefore the whining noise that I started to hear when the grinding noise stopped. If you go to the thread that I started, "grinding noise", I remember being surprised how the grinding noise went away but was replaced by a whining noise!! As all this was going on, particles of plastic/nylon and even a little bit of aluminum started to flow through my engine. It doesn't take much foreign material in the oil to create huge problems and or a tapping engine.

If I knew what I know now about the tensioner being related to the whining and also knowing that it's not that hard to get at it and fix it, I would've fixed it or had it fixed right there and then. I would suspect that there is a good chance that I wouldn't be dealing with a tapping noise if I would've done that!!

Thanks again Krashed, I'll let you know the outcome.

07-21-09, 05:17 AM
Naw, thank you for keeping us updated! This is a good learning experience for me as well... The only thing that kind of worries me is if enough foreign particles went through the oil gallery to get up to the head and partially clog a passage, I wonder how much may or may not have ended up in the main bearings and essential components like that..... I would think that the oil filter would pick up most of the particles; but since there's the tapping noise, it's got me wondering. Hopefully, the problem isn't that big.

Would it be a good idea to drain the oil and give her a good ol' kerosene flush? That would at least get whatever crap there is in the pan out... Then a new oil filter would keep the amount of oil going through the bypass valve to a minimum.

07-21-09, 02:11 PM
Krashed, I've been thinkning about going to an oil change place and have them flush the engine with whatever they have. They have all sorts of snake oil in can at those places, it wouldn't hurt.

I looked pretty good at the bearing surfaces of all the cams and caps, everything looked like it should. There was no eveidence of any metal going through the engine. I wasn't in the bottom end so it is possible there could be a scratch or two in some of the bearings, rod and or main bearing. On the top end there is no evidence of anything like that. I guess it could just be a lifter pumping up and then going back down. I assume these lifters pump up and if so, one could be going bad. My thinking is if there is some blockage, and the lifter I changed with the scarring was the lifter being starved for oil, if I took the cover back off then the new lifter would now have the scarring. There were no other lifters that looked even that worn, they all looked pretty darn good.

I'm still a bit surprised that there has been no other tensioner failures like I saw. Maybe I keep my motor in the higher RPM range than most and thus stretched the chain earlier than others. Then again, maybe there are cars with that grinding/whining but like I had said from the beginning, it's not very noticeable. You can't hear it in the car, especially with the fan runinng or radio on.

I will suggest that if anyone geos onto that timing cover, say to release the tensioners while doing a head job, look at that lower tensioner real good. When looking at it with the engine in the car, it's hard to see the actual slider part because it's up in behind the oil pump. You can see the tensioner pretty good but not the wear part, the slider!

I will get this fixed and now it's not only to get my car running but to satisfy the curiosity that I have in what could be causing this problem!

07-23-09, 01:23 AM
I found out something today that I knew all along but never thought of. I was talking to a fella at an engine shop where all they do is major engine work, on all type engines. I asked him about taking the engine out and replacing the rear main seal, pan gasket and any other related gaskets to insure that I have a nice dry motor when finished. I then asked him about the tapping and how would do they figure out which lifter may be tapping and he said we would do that before we pull the engine. Then it dawned on me, I said, you run the motor with the covers off and he said, yes, that's pretty much the only way to tell unless of course your changing all the cams and lfiters then it doesn't matter which one is tapping.

We did that all the time when I was younger and working on motors with hydraulic cams, That was the only way to adjust the rocker arms so there was the correct clearance. He asked me how the cams looked and I told him all the lobes looked okay although one could be worn a couple of thousands of an inch and I don't have a micrometer to tell for sure, he responded what i've been saying, that .002's of an inch wouldn't matter.

I'm not sure how they would be able to tell because on the motors that I worked on all had rocker arms so you could push down on a rocker while the motor is running and you woudl quiet the tapping lifter form the added pressure and you found your lifter. I'm assuming you can probably see the lifter that's tapping or maybe you can put your ear by them and tell which one because teh noise isn't be transferred across the cam cover.

I may just pull the front cover and start the motor just to have a look. I took the oil cap while it was running today and I could see oil drips coming off that first lifter. The drips weren't falling straight down off the lifter but rather squirting sideways about an inch from the lifter so it looks as though there is decent oil pressure at least to the first lifter.

I really need to get the rear oil seal replaced so I"ll probably end up taking it there and have them do a few things to the motor. I asked him abotu head gaskets and he said they use inserts and head bolts from a 5.7 diesel motor, I think it was a 5.7 diesel, could've been 6.7 doesn't matter, that's what they use and I doubt I could talk him into studs. He daid say they do quite a few N*s and haven't had any come back. They give a 3 year 36k mile warranty so they're pretty confident in their work.

If I do all that, I'll probably have them balance the motor and mill the heads if there's clearance to do so. This engine shop also builds race motors so they have all the equipment to do this. When I used to build motors, the one thing I did or had done that I feel made the biggest difference in the performance of a motor, that is with all things equal, was to balance the motor. Take 2 stock motors and balance one of them, I guarantee you the balanced motor will outperform the unbalanced motor hands down, not even close. I figure with the motor balanced and the heads milled a few thousands I should gain an easy 10% in BHP.

Any comments and or suggestions would be appreciated.....

07-23-09, 09:26 AM
Milling the heads won't accomplish anything - a cleanup cut of maybe .002 or .003 IF necessary. There's a pretty thin quench area in the combustion chamber and practically no deck height, so be careful.

Without the front cover there's no balancer, so no oil pump drive. Start the engine and 0 oil pressure.

If they use Norm's Inserts and new bolts.......OK. NO Helicoils !!!! Show them Jake's website. www.northstarperformance.com

The cranks are dynamically balanced when machined and the piston/rod assemblies are statically balanced. Not sure about the torque converter.

The hope of a 30 HP gain from balancing and a head cleanup is a bit much...........too damn many electronic controls factor into the equation, too. Heavier valve springs to raise the valve float RPM won't work, either - you're already cupping cam followers as is, and the Northstar cams are already on the edge of lobe pressure capabilities. The cam curves are already falling off above 5500 RPM, so you might gain a few hundred by advancing the entire valve train about 4 degrees.

07-23-09, 01:51 PM
Submariner, appreciate your response although you may have misunderstood what I wrote or maybe I didn't explain myself. When I say start the engine with the covers off I mean the cam covers, not the timing cover. When I said pull the front cover, I meant the most forward cam cover, which is obviously the easiest to get to.

As far as balancing the motor, I couldn't find any documentation to indicate how the motor was balanced if at all from the factory. I do know you can realize a tremendous difference with a balanced motor, I guess it depends on far out the motor is or how well it has been balanced fom the factory. The old fella that used to balance my motors always said, if there is a 2 gram difference in the pistons from lightest to heaviest, ( 2 grams = approx. weight of 1 penny ) at 7k RPM's it would be like trying to take a 20 lb. weight at the end of a 10 ft. rope and swinging it around your head. Back then a lot of factory pistons would still have excess slag on the underside from the casting and you could see where someone would grind off a little slag to clean them up, would they balance each psiton, no. It always seemed as though cast pistons were pretty far out where as forged psitons were closer to equal weight. I imagine the N* has forged pistons but to be honest, I really have no idea.

Your response on the heads is what I was after, could they be milled to raise the compression a bit? Your answer indicates there isn't enough material to do that. So you know, I wouldn't consider trying to raise the compression ratio much, if the ratio is like 10:1 I would aim for 10.5:1 no more than 11:1! I'm a firm believe that the drive train on these cars are equal to the task which is holding up to approx. 300 HP. Could you go to 330-350 HP without having drive train problems, I believe so. If you were to go over 350 HP, then your more than likely asking for trouble. How you drive the car will change what I just said and to be more precise, I'm talking about driving the car WOT from rolling starts with occasional dead stopped starts. While in WOT, let the transmission shift on it's own, no forced shifts.

I also believe that if you were to go much over 350 HP, then your looking at potential bottom end problems. I agree that the valve springs are a limitation, they are what they are and changing the srpings without different cams would be futile. I have looked for aftermarket cams and could not find any available, nor any other engine parts. The reality is that your very limited to what you have, that's why I felt like balanceing the motor is one area where you could gain some real HP, that and raising the compression just a little bit.

I will mention Jakes website and tell them about the inserts. I have a feeling from talking to them is that they have the, "this is how we do it syndrome". There are lot of people who are like that and that's okay although I believe that one should always be able to compromise and should always be looking for a better way/suggestions, especially if your in business with the public. There are several engine shops around so I'll call some others and see what they say. I did call a second shop that told me kind of matter of factly, I don't mess with N*. I said, your pulling my leg and he said "no", I don't mess with them, they are to hard to work on. People are so misinformed and really don't know any better. So many garages say that and most of them probably have never worked on a N*. I thought it was one of, if not the simplest engine that I've ever pulled a timing cover on.

Like always, appreciate the response...

07-31-09, 12:51 AM
I finally recharged enough to have at it again so this time I removed the cam cover on the front bank and started the motor to see what I could see if anything. One thing is certain, I don't have an oiling problem or lack of oil getting to the lifters/cams! There was oil flying all over the place and that was pretty much at idle, when I revved the motor a little, the oil was flying over the front end of the car. I had placed some rags across the front just above the exhaust manifold expecting the oil to dribble over the bottom edge of the head and onto the rag. I suspect at least 1/4 to a 1/2 qt. of oil leaked out in about 1 minute, maybe 2 minutes of run time.

With all the oil spilling out on top of the lifters it's virtually impossible to see anything out of the ordinary. Everything looked okay but I said that the last time I looked at the lifters and cams although they weren't moving the last time I looked. After I shut the motor down I looked at all the lifters, one at a time by turning the motor over maybe 1/8th of a turn at a time. The only ting I noticed was the 1st lifter on the intake cam appeared to have a hairline crack about 3/16-1/4" from the outside perimeter of the lifter. The only way I can explain it is a circle within a circle with the inner circle like I said, about 3/16-1/4" inside of the outside perimeter. The scratch or fracture is about 1/2-3/4" long so it doesn't even come close to stretching around the circumference of the lifter. If it is a hairline fracture, I would guess that would cause the lifter to lose pressure and not "pump up", assuming that these lifters do pump up.

The tops of the lifters look like mirrors and the cam lobes also look vitually perfect. I've seen some pictures of worn lifters on this website, mine are nothing like those. Those worn lifters must've been driven with them banging and or tapping for a long time. I figure it like this, a lifter and or cam, or both, have to wear wuite a bit before you'll hear a ticking which when there is way to much clearance, turns into a tapping. I never heard a ticking, the motor went from perfectly quiet, to a tapping. That's why I believe I have a failed lifter, not a worn lifter, but a failed lifter, if that's possible. I don't know for sure that these lifters "pump up", althoug I would assume they do. If that is a crack I discovered on the top of that 1st lifter, that would explain the "all of a sudden tapping".

I loked at it awhile and just didn't have it in me to take the front of the motor apart again so I could change that lifter. I'm going to take it to a motor shop and let them wrestle with it, I can't remain bent over the motor for any length of time because my back and legs start hurting to much. I did it once, that was enough. The motor will be coming out because any oil leaks will be fixed, I want a dry motor when this is all said and done. I have aleak now which I was told by the dealer that it was a rear crank seal. Any suggestions on oil leaks and where these motors tend to leak oil. Mine appears dry from the top on down, past the halfblock, it's still dry. I see somemay be comeong from the pan gasket, the rear crank seal and for sure somewhere around the oil filter. It's a little wetter around the oil filter area, there's a sending unit right in that same area.

Comments, suggestions would be welcomed........

08-30-09, 10:25 PM
I haven't read over this post in quite awhile so I may duplicate some pictures or comments, I'm in the process of changing several lifters which will give me a better chance of getting the bad lifter change. I believe I mentioned previously about marking the cam gears on the backside so you can look from the opposite side of the car to check your cam timing. I've attached a couple of pictures showing the way I marked the cams with some of my daughters finger nail polish. For the first time, I've also included a picture of my 94 STS which is a fine, fine, automobile. I'm sure some wonder why put in so much work and or money into an older car like this, just buy another car.

For myself, this car has everything I need, a good ride, good handling, pretty fair power and it looks okay, not to mention I paid cash for it many years ago, all good reasons to keep it rolling for several more years!




My car will be running shortly! I believfe Krashed may have been correct way back when I first started, an internal lifter failure! I now believe the tapping is coming form the inside of the lifter and not the cam banging against the lifter itself.

08-30-09, 10:26 PM
The picture of my car was taken about 2 hours ago and is not an old picture from years ago!

08-31-09, 01:40 PM
Beautiful car!

08-31-09, 10:34 PM
Appreciate the comment tateos, it's in pretty good shape for an older car, original paint I may add.

I've started my car and still have the tapping, very confused at this point and getting desperate because my daughter is getting angry with me for having to use her car nearly every day. So far we've managed but I know somewhere along the line we'll have a conflict so I need to get my car running.

Today I located a 98 vin 9 motor out of a Deville, will it work in my STS without to much trouble. Anyone know what year motor will work with little to no problems?

If I change the motor, I'll have mine taken apart to locate the problem which I still believe is a lifter, I guess I should've changed them all!! When mine is fixed and back together I'll have a spare motor which I'll more than likely sell.

08-31-09, 10:52 PM
You can't use a Deville motor in an STS. On is an LD8 and the other is an LD37. You need to stick with a '93 or '94 STS motor.

08-31-09, 11:08 PM
Ranger, the LD8 and LD37 you mentioned are engine model numbers? As of today, I couldn't locate either a 93 or 94 motor, not one that was any good. The Deville motor that I located is low mileage, a vin 9 and of course, they told me that it would work. I questioned them about that and pretty much expected them to tell me that it would work which is what they said. I'm not doubting what your saying, curious how much would have to be changed to make it work if at all possible. Changing an intake along with the throttle body would not be that much trouble if that's where the problem may lie!

09-01-09, 11:50 AM
The difference between the VIN 9 & VIN Y is the intake cam, PCM & final drive ratio. The difference between the '93/'94 and later models is the intake manifold. I'm not sure about the motor mounts. So if the mounts match you'll have to swap intake manifolds and cams.

09-05-13, 05:57 PM
I have to start by saying that this forum is an invaluable source for troubleshooting! A quick search usually has answers for me. On that note:

I suspected timing chain issues when a new whining sound appeared under the hood in my 2000 seville and I realized it wasn't the power steering pump. After confirming it's source (removing the serpentine belt and running it to make sure the noise was still there and listening closely to it's source), I'm ready to dive in and remove the chain cover to access the guide and tensioner pully. Does anyone know if there's a way to avoid removing the motor mount that slightly covers the timing cover? I replaced that mount a few months back and it was a bear...

Thanks in advance!