: Northstar Camshaft Wear - Common? Cause?



Mark D
11-29-11, 12:36 AM
New member here. I hope this topic isn't already covered. If it is, I apologize.
I have seen Northstar engines with this same symptom, and am wondering about it. I'll get into why I'm wondering in a minute.
It seems that the exhaust cams wear dramaticallly, showing both lobe wear and tappet wear. But not on all lobes and not on all tappets. It seems to usually be the tappets toward the middle of the head that show the most wear. Yet, these engines were, and are, perfectly good running engines. Were it not for my being aware of this wear, I'd think the engine was in great shape.
The intake cams don't seem to have this issue. Strange, isn't it?

I am currently doing head gaskets on a 98 Northstar engine, and it has this, what I see as, typical cam wear. This is my wife's car. I did head gaskets about 7 years ago, knowing that I'd probably have to do them again at some point. At that time, there was no really good fix for the bolt problem.
This time, I'm using studs, and it shouldn't be a problem anymore.
Last time I did the gaskets, the car had less than 100 K miles on it, and I did not notice much lobe wear. This time, it has the lobe and tappet wear I mentioned.

Yet, if the head gaskets hadn't started to leak again (three bolts came out with the aluminum threads still stuck to the bolts - no surprise) I would have expected this engine to run indefinitely.
It looks like iminent cam failure. But is it? Is this a sort of normal thing that I can just ignore rather than have to spend 800 bucks on two new exhaust cams?
That is my question. Just how serious is this really? I'm thinking of replacing the right side cam with new, and let the front go because it wouldn't be too difficult to change with the engine in the car.
Wondering if anyone has any helpful comments on both the cams, and my plan.
Thanks so much. I should add that the car now has a little over 200 K on it.
Mark D.

maeng9981
11-29-11, 04:52 AM
Before 2000 the Northstar engines used flat tappet type cam followers. This type of cam followers wear out with today's oil with less ZDDP/anti-scuff package in it.

This is the main reason why many members here will suggest to use a HD/Diesel rated 10W-30 to your 99- and before Northstars. These oils carry higher anti-scuff/anti-wear package and perfectly OK to use diesel rated engine oil to a gas engine. They do not have those "starburst" logo because it will not meet the environmental reguations. 00+ went with roller cam followers and do not suffer these problems.

Make sure you are using a 10W30 too. No fancy oils like 20W50.

Ranger
11-29-11, 11:13 AM
Yet, if the head gaskets hadn't started to leak again (three bolts came out with the aluminum threads still stuck to the bolts - no surprise) I would have expected this engine to run indefinitely.
It would have if you had used inserts or studs the first time.

89falcon
11-29-11, 03:04 PM
New member here. I hope this topic isn't already covered. I
It seems that the exhaust cams wear dramaticallly, showing both lobe wear and tappet wear. But not on all lobes and not on all tappets. It seems to usually be the tappets toward the middle of the head that show the most wear. Yet, these engines were, and are, perfectly good running engines. Were it not for my being aware of this wear, I'd think the engine was in great shape.


About 20 years ago, I had a 1972 Vette that I'd done a considerable amount of work on.....Doug Nash 5 Speed, ported & polished heads, MSD, headers, intake, cam...you name it.....

The cam was of a longer duration and higher lift than stock, so the car had a little bit of a "loppy" idle.....
While doing some other work on it, I hooked it up to one of the better engine analyzers of the day....one that shut down individual cylinders and compared the drop-off in RPM's.....all of my cylinders had almost identical drop-offs at idle....except 1......it had a MUCH higher dropoff.....meaning that cylinder was MUCH stronger than the others.....at idle......about the same at midrange.....and much less at the upper RPMs....
I took the engine apart....and guess what...the cam lobes on THAT CYLINDER ONLY (may have only been one lobe....don't remember if it was exhaust or intake) were trashed, along with the lifter(s).

The moral of the story? An engine designed to run at lower RPMs will typically have a much shorter duration and a lower lift than a high RPM engine. This means when you lobes wore down, they may have even HELPED off-idle power/torque....but at the expense of higher RPM power.....and if your car is like most Cadillacs, it doesn't often see north of 4000 RPMs......

Makes perfect sense to me!! And my 72 Vette? I ran a new oil in it....only the best!!!! Mobile One synthetic.....oooopppppssss....and until coming to this forum again after a break of 5 years, that's all I ran in my 97 STS....and yes, I had a couple worn lobes...

Not sure that it matters, but The exhaust valves do get hotter than the intake valves....and may transfer some of that heat to the lifters....which may cause what little anti-wear protection the new oils have to break down quicker on that surface....:hmm:

Mark D
11-29-11, 03:10 PM
Well, I have known about the oil problem for a long time. But I associated it with high performance engines with high lift cams and king kong springs. I just had this idea that an engine like this, with featherlight springs and low lift would do just fine. I've been running 10W-30 Valvoline Max Life summer and 5W-30 winter. I think I'll switch over to Brad Penn oil. It's not cheap, but it's the best bet of them all.

And with regard to hindsight in inserts and studs; At the time, there was no information that I could find with regard to studs. Inserts were pretty much using the factory inserts. I had just come off a similar engine that had to have inserts. The common knowledge at the time was that when the inserts pulled out, and they often will, the block is junk because there's no fix for that.
So, inserts were considered a repair for stripped threads, not something to do as a precaution. The heads seemed to torque up just fine. But the problem is, when you're using that stupid torque angle procedure, and you're turning the last few degrees on the bolt, you really can't tell if the bolt threads are climbing over the block threads or tightening. You're just turning until you reach your magic number.
This time I am using the studs from Northstarperformance. They go to a 5/8-11 thread. They send a killer drilling/tapping jig along with the studs, drill and tap. If anything goes wrong, I have a spare engine around I can use the block from. I don't expect anything to go wrong, but it always can. It's really not as simple a procedure as it might look like. Extreme care is required.
And, as far as running a long time if it hadn't blown the gaskets again, from what these cams look like, probably not. I'd still have had to deal with this.


So, my question is, how many Northstar engines are running around out there with close to 300K miles and have well worn tappets (followers) and just keep on going? I hate the idea of spending roughly $400 X 2 on new camshafts if these will run another 3o to 50 thousand miles. By that time, my wife will have long since killed the car anyway.
So what is the experience with this problem among those who have maybe disassembled engines with far more miles on them?

Worse, she's driving my '95 until I get this done! And that car, to me, is a keeper. It probably has exhaust cams that look just like the others. All worn out lobes and tappets. But it's quiet and runs perfectly. And has never needed head gaskets. Yet.

Did I mention that I really hate doing this job? :)

Mark D.

Mark D
11-30-11, 10:15 AM
Well I think I know why the exhaust wears out but the intake doesn't. Or at least not as much.
I took a look at the cams. The exhaust cam has a much steeper ramp angle than the intake, which has longer duration. This puts considerably higher stress on the nose of the cam lobe and the lifter. That part's solved. Still to come is how far it'll go.
I'm going to install a new exhaust cam on the right bank because it's pretty tough to change that one with the engine in the car.
The left bank still isn't exactly easy, but it's nothing like changing the right bank exh cam.
So I'm going to leave the left cam as it is and see how far it'll run before it goes flat. I just have to know, I guess.

Later on today I'm going out to buy a well used, poor condition, '95 Seville SLS that a guy's trying to dump and nobody will buy.
I'll let my wife drive that until I get her's back together again. Waiting for parts will make this job last at least two more weeks.
After that, it'll become a parts car.
Mark D.

89falcon
11-30-11, 10:24 AM
Well I think I know why the exhaust wears out but the intake doesn't. Or at least not as much.
I took a look at the cams. The exhaust cam has a much steeper ramp angle than the intake, which has longer duration. This puts considerably higher stress on the nose of the cam lobe and the lifter. That part's solved. Still to come is how far it'll go.
I'm going to install a new exhaust cam on the right bank because it's pretty tough to change that one with the engine in the car.
The left bank still isn't exactly easy, but it's nothing like changing the right bank exh cam.
So I'm going to leave the left cam as it is and see how far it'll run before it goes flat. I just have to know, I guess.

Later on today I'm going out to buy a well used, poor condition, '95 Seville SLS that a guy's trying to dump and nobody will buy.
I'll let my wife drive that until I get her's back together again. Waiting for parts will make this job last at least two more weeks.
After that, it'll become a parts car.
Mark D.

Just so you know....the exhaust cams from the 95 SLS are the same as your 95 and 98 STS exhaust cams....

Submariner409
11-30-11, 12:01 PM
So, my question is, how many Northstar engines are running around out there with close to 300K miles and have well worn tappets (followers) and just keep on going?

We have seen pictures in here of pre-2000 followers that have actually been worn to the point that the valve tip is sticking through the bucket. Earlier this year and more earlier than that. Needless to say, the associated cam lobe(s) were also trash.

Flat tappet wear is not restricted to Northstars, though..........and, for what they are, they still run decent open spring pressures and lift measurements.........but the 4 valves and pent-roof semi-hemi chamber design don't need radical lift numbers.

Mark D
11-30-11, 01:32 PM
Thanks on the info about the cams on the SLS and the STS. Only thing there is that that SLS is so well used that I don't hold much hope for those cams being in very good shape.

I found this site - Maybe you long time people already know about this. Called Cadillac Hot Rod Fabricators, or CHRF. http://www.chrfab.com/cam_shafts1.htm That link goes to their own camshafts. I can buy four from them for about the price of 1 1/2 cams from GM. They make some claims, maybe inflated but maybe not. They show a line of cams that don't specify any lift, but show durations (probably intake, they don't specify which cam has what) that range from 272 degrees up to 310. I haven't a clue what the original cams are, so I can't compare. But that 310 looks interesting. I have no plan to use it in this application though.
They also sell new springs, and understandably. According to them, the stock seated pressure is 48lb for the 275 hp and 59 lb for the 300 hp while theirs is 100 lb. And for what they call factory lift, the same figures are 98 lb, 109 lb and 180 lb. I'm sort of thinking about their 272 degree cams. Probably won't go that route though.
With regards to the spring pressure comment I made in an earlier post, I was not knocking the spring pressure on the Northstar engine, it is what it is and that is what it needs to be. I was only commenting that originally I was sort of surprised to see that sort of wear with such low spring pressure. However, with a lobe like that exhaust one, I can fully understand. I'll just use better oil from now on. Interestingly, I have a pushrod engine I built for racing back in 1982 that I raced for 7 years, then stored for about ten years. Then I needed an engine for a Suburban, thought of that engine, stuffed it in and am still running it. Interestingly, though it has a fairly high lift cam and, though I forget the original spring rating, roughly 250pound springs, and I'm using whatever oil I can find in it because I don't care much about it anymore, that old girl just keeps on going and going with no indication of cam trouble. I have put a little over 85000 miles on it since the racing (oval track) and storage. Some engines hold up with the "crappy" oil we have today, and some don't. I think these Northstar engines do fairly well, as I don't see much wear until they have fairly high miles anyway. Most people throw their cars away by that time, don't they?

Oh, on that SLS, it's shot. Engine drips oil from everywhere, and only showed a bit on the bottom of the stick when I looked at it. That oil was pure black. Windshield is cracked, interior is worn and parts broken or missing, dents, typical salt rust, horrid looking wheels, tires pretty well used up, and worst, it had a list of codes so long, like every PCM code there is (just about) There were so many I didn't bother to read them all. I just cleared them and decided to see what comes back. They were all in history, not current. I'm going to look at it again today and make up my mind. It's cheap. It runs. It has a Northstar engine that can be parts or used elsewhere.
Mark D.

Submariner409
12-01-11, 09:23 AM
CHRFAB has been posted, discussed, talked about, tried many times in these threads. They do some neat stuff for stand-alone managed Northstars in Fiero kit cars and sand rails. Practically nothing for our PCM-managed FWD drivetrains. If you take their "270" cam specs at .006" lift and compare them to the same cam at a running timing check of .050" you'll see that they're nowhere near radical - a nice, manageable street re-grind.......and our 1998+ PCM's can't take advantage of the cam possibilities, so we're back to Square One.

All this was discussed at great length, with posted timing cards and sprocket moving discussions last spring. It's all still in here somewhere. One of our members, AJXTCMAN, a Cadillac Tech, has done a slew of work on the northstar ECM's and PCM's and has come up with precious little for the 1998+ PCM cars. I believe that he is now involved in a side enterprise, pcmcalibrators, that is doing work on pre-2000 electronics. AJ has done some cam work.

Mark D
12-01-11, 11:34 PM
Thanks for the reply. Funny you should mention reground cams. Just today I started thinking about doing that with my cams, after finding someone who I believe can do it right.
Also found an oil additive that should allow me to continue to use off the shelf motor oil but without the cam wear. I'll post more on it when I get my info together.

Mark D.

Ranger
12-02-11, 12:48 AM
This stuff? ZDDPLUS

http://www.zddplus.com/imgs/zddplus_4oz.gif

Submariner409
12-02-11, 10:09 AM
You can also take a look at the Joe Gibbs Racing and Edelbrock websites - for HD oil formulations. BUT, be careful: indiscriminate use of oil additives and dedicated high load ZDDP oils will ruin a catalytic converter.

For an "off the shelf" conventional HD oil that is satisfactory and safe for your two pre-2000 Northstars, simply shift to Shell Rotella or Pennzoil LongLife 10W-30 oils.

If you're a synthetic oil person, another way to skin the cat during an oil/filter change is to blend in a quart or two of a EURO spec synthetic oil or a Joe Gibbs HR synthetic 10W-30 - both types have an increased ZDDP load and the blend would not exceed the older SJ or SL oil specification for additives - that spec was perfectly OK for catalytic converters 10 years ago.

Google "api motor oil specifications" and open the Wikipedia page. Deep reading...............

Go to www.joegibbsdriven.com (http://www.joegibbsdriven.com) , open the home page and click on the "Training Center" tab. Read the articles in the left column.

Mark D
12-06-11, 07:05 PM
Well, I'm still looking around. No rush, and that's good because I'm pretty busy with work.
But so far, I'm looking at a product called Oil Extreme http://www.oilextreme.com/oil1.html
It is recommended by David Vizard, and that's a plus. Not sure about how it might affect a catalytic converter.
It seems to me I read that even the diesel (Rotella included?) oils are also sans the zinc whatever stuff that the EPA decided was a bad thing, thus are not as good for flat tappet cams anymore as people might think. That's what keeps me away from those oils. Otherwise, I could use a 5W-30 Rotella, if I can find it. I usually only see it in heavier grades. No, I can't use 10W-30 in winter. I do need the car to start, and even if it were to start with 10W-30, the bearings wouldn't last too long. Sometimes even 5W-30 is a bit too heavy and I wish I was using 0W-30. In summer, 10W-30 is fine. I change to that in summer.
Otherwise, Brad Penn is excellent oil and shouldn't be a problem with a catalytic converter, AFAIK. I can get that locally, though expensive. But what oil isn't expensive anymore? :-)

Also, with regard to regrinding the cams, I'm looking at having a well known cam grinder, Mike Jones, grind them. He says he's reground a lot of Northstar cams. No problem, apparently. I was worried about loss of base circle and lifter contact. But I guess that'll all work out fine. Still looking into that, too, though. No final decisions yet.

But the block is drilled and tapped. It's waiting for me to get some gaskets. I've put it back on the "shelf" again for a while. Work comes first.
That's why I bought that crappy SLS. Gives the wife something to drive while her beloved red STS sits up in the air with all its guts ripped out of it.

Later
Mark D.

I should add, I can't really go to a lot of web sites to read information that I should read because I'm on a realtively slow dial-up connection. It takes to darn long to do that. I can leave my machines out in the shop for a short time, but not long enough to check a lot of links. The wikipedia link above is one that I'll read. I know I need to know more about the current oil situation. All I reallly know is that it's not good for some applications.

Ranger
12-06-11, 09:28 PM
No, I can't use 10W-30 in winter. I do need the car to start, and even if it were to start with 10W-30, the bearings wouldn't last too long.
Where in the world did you get that idea from?

The Northstar was tested with 10W30 in Kapuskasing, Ontario at -40F. I have yet to use anything but 10W30 (in this or any previous car). Starts and runs just fine even in below zero weather. 91,000 and counting.

Submariner409
12-07-11, 09:23 AM
No, I can't use 10W-30 in winter. I do need the car to start, and even if it were to start with 10W-30, the bearings wouldn't last too long. Sometimes even 5W-30 is a bit too heavy and I wish I was using 0W-30. In summer, 10W-30 is fine.

That ^^^ is very incorrect. Multigrades are exactly why you can run them in some fierce cold weather. IF the ambient temperatures are consistently below about 10 degrees F you would be just fine with either 0W-30 or 5W-30. Above that point, then the recommended 10W-30 (for those pre-2000 engines) is fine.

David Vizard has been offering automotive advice for a long, long time. BUT, casual use of engine oil additives (especially the ZDDP concentrates) runs the very real possibility of permanently damaging the catalytic converter.

Mark D
12-07-11, 02:00 PM
Please explain just where I am incorrect in my statements.
You yourself just said that a 0W-30 to 5W-30 is what should be run in winter, as did I in my post above.
I can't say for sure just how a Northstar engine would handle molasses (10W-30) in -20 or colder weather, but when GM recommends 5W-30 in cold weather, I think they know what they're talking about. But when you canít even pour it out of the bottle, Iíd say itís a bit stiff for starting the engine, eh? AAMOF, at -20 even with 5W-30, my Northstar engines have a difficult time cranking. They are very stiff. At -30, even the transmissions donít like to wake up. Cold weather starting ainít good for anything, but light oil sure helps.
With regard to bearings, that is exactly the issue that can crop up. If you force the engine to run when the oil is too stiff to pump, the bearings will not be seeing the oil film they need. True, there is residual oil on the journals. But I have personally heard the hard knocking an engine makes when it is forced to run on heavy oil in cold weather.
I do run a 10W-30 in warm weather, and that's all the more viscosity the engine needs.

More on cam grinding. I'll be shipping the two exhaust cams (I'll pick the two least bad cams) out today for regrinding. The grinder says he can change the profile just a bit so they won't wear so badly on the lifters, and at the same time won't affect performance. This is not the final word though.
But if that is the way I go, I won't have to worry about oil.
AAMOF, when I think about it, I don't really have to worry about it anyway. After all, the engine made it to nearly 200,000 miles before I noticed cam/tappet wear only because I took it apart from a head gasket issue.
I think I could put it back together with new lifters and a reground cam, or even a OEM cam, and it would run for the rest of the life of the car.

Mark D.

---------- Post added at 03:00 PM ---------- Previous post was at 02:38 PM ----------


Where in the world did you get that idea from?

The Northstar was tested with 10W30 in Kapuskasing, Ontario at -40F. I have yet to use anything but 10W30 (in this or any previous car). Starts and runs just fine even in below zero weather. 91,000 and counting.

I donít have the advantage of knowing exactly what GM found out when they tried to start the engines with 10W-30 at forty below, and Iím sure they arenít about to tell me.
But starting in those temps and living a long life doing that year after year surely doesnít seem likely to me. AAMOF, getting it started at all seems like a miracle, because with 5W-30 in the things, they barely crank over after sitting for a night or two and all the residual heat is gone.
You can do what you like with your engine, but Iíll run 5W030 winter, considering 0W-30, and Iím sure the car will do just fine. In any case, that oil viscosity isnít going to affect the cam wear, which is the topic of the thread. But with oil in winter, my main concern is to just get the thing started.

In this area, low temps in winter from late December until mid to late February typically run anywhere from +/- 0 to 35- 40 below zero. Highs will climb to sometimes only -20, but other times to single digits above 0. There are warmer days interspersed, and nobody can say what the weather will be five minutes from now. But I tend to want to prepare for the worst, which means at least 5W-30 for sure.

I havenít responded to the comments about catalytic converters and additives because I havenít decided just what I plan to do yet anyway. The advice is well taken, though.
Mark D.

Ranger
12-07-11, 04:23 PM
Do you realize that GM only started using the 5W30 in the 2000+ Northstars and that the pre-2000's where spec'd for 10W30?


But starting in those temps and living a long life doing that year after year surely doesn’t seem likely to me.
Don't you wonder how engines survived before 5W30 came about? I don't know how old you are, but unless you are very young you should remember that 5W30 has not been around for all that long. I'm not trying to tell you what to use. Use what you are comfortable with. Just saying that using 10W30 in below zero temperatures WILL NOT kill the bearings or do any damage. It is no colder Minnesota than it gets in Northern Illinois and my cars have survived many, many brutal winters on 10W30 and lived on for many, many years afterwards.

89falcon
12-07-11, 04:55 PM
Do you realize that GM only started using the 5W30 in the 2000+ Northstars and that the pre-2000's where spec'd for 10W30?


Don't you wonder how engines survived before 5W30 came about? I don't know how old you are, but unless you are very young you should remember that 5W30 has not been around for all that long. I'm not trying to tell you what to use. Use what you are comfortable with. Just saying that using 10W30 in below zero temperatures WILL NOT kill the bearings or do any damage. It is no colder Minnesota than it gets in Northern Illinois and my cars have survived many, many brutal winters on 10W30 and lived on for many, many years afterwards.

Yep! Only 20W50 Castrol for my 1970 MG!!!

Ranger
12-07-11, 09:05 PM
Actually I can take it a step further. Back before multi-grade oils we did oil changes every fall. Took the straight 30 out and put a straight 20 in for the winter. Bearings seemed to survive then too.

Submariner409
12-08-11, 08:05 AM
Heh, heh, heh..........Yeah that ^^^

I still have an unopened metal can of SAE 30 motor oil in the shop: Quaker State Refining Co., Oil City, Pa. USA. (Not 30W - SAE 30)

30 in the summer, 20 in the winter. April and October. "Kendall - the 2000 mile oil"

Mark D
12-08-11, 07:12 PM
Do you realize that GM only started using the 5W30 in the 2000+ Northstars and that the pre-2000's where spec'd for 10W30?


Don't you wonder how engines survived before 5W30 came about? I don't know how old you are, but unless you are very young you should remember that 5W30 has not been around for all that long. I'm not trying to tell you what to use. Use what you are comfortable with. Just saying that using 10W30 in below zero temperatures WILL NOT kill the bearings or do any damage. It is no colder Minnesota than it gets in Northern Illinois and my cars have survived many, many brutal winters on 10W30 and lived on for many, many years afterwards.

Eh, that is entirely incorrect.
The service manual and owners manual for the 1995 Cadillac both call for 5W-30 or 10W-30, depending on tempratures.
If you have a service manual handy, you can find it on page 0B-2
They specify 5W-30 when the temprature will not be over 60 degrees. You wouldn't want to use it in Arizona, IOW.
Also, since nobody wants to believe me, the manual specifically states: " NOTICE Using oils of any viscosity other than those viscosity's recommended could result in engine damage. When choosing an oil, consider the range of tempratures the vehicle will be operated in before the next oil change. Then, select the recommended oil viscosity."

That is exactly what I do. I don't care if you folks do it or not with your cars, it ain't my car.
And just to set the record straight, northern Illinois can get very cold. But I'm sorry to say that it is not consistantly as cold as it can get on the midwestern and western plains of Minnesota. Our temps in this area are very similar to those of Fargo N.D.

Oh,
With regard to age, and 5W-30 hasn't been around all that long.
I don't know just how long "all that long" is, but it was easily available in the 1960's and we used it then, as now, to make sure the car would start.

You guys who live in the south probably wouldn't understand, so I'm not taking this any farther. It's pointless. The engine WILL be run on 5W-30 in winter, as GM recommends. which is a multi-grade oil designed for winter for the person who explained to me what multi-grade oils are for, and yes, I know full well what multigrades are for.
Those who dont' think multigrade oils are good for winter starting can still buy straight 30 oil easily. You can even get straight 50 if you want.

I will admit that it took me a while to come to terms with using lighter weight oils, like 5W-30. But by the mid '70s I was a convert. It's not for summer unless the car maker says it is.
Mark D.

Submariner409
12-08-11, 08:47 PM
Cum Romanum venio, ieiuno Sabbato; cum hic sum, non ieiuno: sic etiam tu, ad quam forte ecclesiam veneris, eius morem serva, si quiquam non vis esse scandalum nec quemquam tibi.

More lately devolved into the more popular "When in Rome, do as the Romans do."

Oil wars are fun..............Now, if I were driving my STS in Siberia in February...................or McMurdo Station in August.........

Ranger
12-08-11, 09:45 PM
Mark, you are missing the point. I am the LAST person to tell anyone what oil to use. If you go back and look at my posts in any "What's the best oil to use" thread you'll see that. By all means use what YOU are happy with. The only point I was trying to make is that your comment "even if it were to start with 10W-30, the bearings wouldn't last too long", is dead wrong.

Mark D
12-09-11, 12:30 PM
Ok, I will partly agree with what you said. I think I came across as saying that the bearings would die from a cold start, or a few cold starts. This, of course, is not true. But over a period of years, it does have an effect.
But what I neglected to mention was the effect a cold start, and I don't mean a "cold" start at +20 degrees F, the cylinder walls suffer more than the bearings will. They depend on splash oiling from the crank. When the oil is heavy and stiff, there is not much oil flinging off the crank throws and rod ends. Thus, the cylinder walls run fairly dry.
And you might want to look back at my previous post where GM warns about using oils of other than recommended viscosities. In other words, where they recommend 5W-30 in cold weather, they are NOT recommending 10W-30 in those lower temperatures. Therefore, the use of 10W-30 in cold temperatures is NOT recommended by General Motors.

In any case, all the hyperbole about running heavy oil because it is better for the engine is simply incorrect. It is not better for the cams if it doesn't have zinc in it, and it is not better for any part of the engine than, say, 5W-30. Most especially if you want to accept the word synthetic. I embrace synthetic oils, though some people don't. I don't always use them, but they have come a long way from the early synthetic's, which I shyed away from.


I think that my best option, and what I would recommend to most people who might replace a cam in a situation similar to what I'm doing, would be to use an additive, whether zinc containing, or with some other material that adds extreme pressure properties to the oil, during the cam break in period and until the first oil change. I seriously doubt that use of a zinc additive for a short period of time would cause any harm to a catalytic converter, unless that engine burns an awful lot of oil.

I will be breaking my re-ground cams in using the normal procedure that has worked for me for decades, and that will be to fire the engine up ready to run so I don't have to shut it off. Run it straight to at least 1800 rpm and keep it there for about 20 minutes. This, with additive in the oil. I won't bother with using a zinc containing oil such as Brad Penn. I think in this case I will be just fine with a good additive.
After the breakin period, I'll just use the oil I've always used. My Northstar engines have given me a lot of good miles using oil that does not contain zinc additives, so I have no reason to believe that when this engine goes back together that I won't get just as many miles again. If it doesn't last, I don't think it would be for lack of zinc in the oil. I expect it to give me at least another 50K, maybe 100K miles. That's about as far as the rest of the car is ever likely to go, maybe a lot farther than the car itself is likely to go.


BTW, for the heavy oil folks, a comment was made above about GM and 5W-30 oil recommendations. I'll add to that by saying that GM was recommending 5W-30 for all year 'round in some vehicles back in the 1980's.
I don't remember just which ones at the moment, but one venerable V6 was one of them.

Mark D.

Submariner409
12-09-11, 06:40 PM
I will be breaking my re-ground cams in using the normal procedure that has worked for me for decades, and that will be to fire the engine up ready to run so I don't have to shut it off. Run it straight to at least 1800 rpm and keep it there for about 20 minutes.

Yep...........right on the money ^^^, even with new flat-tappet hydraulic cams. I use a fair amount of Edelbrock or Torco break-in lube on the cam and lifter faces and generally run a 10W-30 Rotella or Pennzoil LongLife for the first 100 hours.

At the first oil/filter change I cut open the filter, remove and squeeze the media in a vise, and open the pleats to see what's trapped there. Sending an oil sample after the break-in oil change is useless - the amount of metals and crap then in the oil is no basis for future comparison.

Ranger
12-09-11, 11:59 PM
Sorry for the late response, but I was out trying to lower the duck & goose population all day.

Now before I go any farther, I want to make it clear that we agree to disagree. This is a friendly debate and I do not want it to get out of hand or taken any other way.

I have stated that I still use 10W30 and always have. What I have never said before is that I will NOT use a 5W oil. Understand that I AM NOT trying to convince you (or anyone else for that matter) to change your choice of oils. What I am about to say is strictly my opinion and belief. Mark, you may have heard mention of the "Guru" (maybe not since you are new). He is a GM powertrain engineer that was involved in the development and testing of the Northstar. One time I asked him if I could still use 10W30 in the Northstar and stated that I felt that the only reason that GM recommended 5W was to appease the tree huggers, the EPA and CAFE requirements and if left to their own choice, GM would still prefer 10W30. Being a (loyal) GM employee he could not (would not) come right out and say it, but if you read between the lines he agreed with me. Secondly, as I mentioned the Northstar was tested at -40 with 10W30 (he was there for that) and 5W30 was not recommended until 2000. Do you know why? 5W30 could not stand up to the shearing affect of the flat tapper rubbing element lifters of the pre-2000 engines (I think both oils had the same amount of ZDDP at any given time). It was only after GM went to the roller followers in 2000 that they where able to use 5W30 (his words, although maybe not verbatim) and put a smile on the tree huggers and EPA's faces. Now that tells me that 5W oils are running near their limit of cold temperature protection. I don't know what other conclusion you could come to. Since the 10W oils have been proven at such low temperature extremes IN A FLAT TAPPET RUBBING ELEMENT engine, I feel very safe with it. I would even go so far as to argue that you actually have LESS cold weather protection with a 5W oil (0W oils simply scare the hell out of me). Now, having made my case, are you going to do any damage or suffer an oil related failure by using 5W30 or me by using 10W30? Nope, we are debating theory. So that's my story and I'm stick'in to it (and 10W30 of coarse).

Oh, one more thing regarding the cylinder walls running dry and suffering more than the cams, here is a picture of a 130K Northstar cylinder wall. I am pretty sure it was of a pre-2000 engine run on 10W30. Note the factory crosshatch hone marks still in it. I think you'll find yours the same when you open it up.


I think that my best option, and what I would recommend to most people who might replace a cam in a situation similar to what I'm doing, would be to use an additive, whether zinc containing, or with some other material that adds extreme pressure properties to the oil, during the cam break in period and until the first oil change. I seriously doubt that use of a zinc additive for a short period of time would cause any harm to a catalytic converter, unless that engine burns an awful lot of oil.
I could not agree more.

Mark D
12-10-11, 12:19 PM
Yeah, well my 200K Northstar engine in the '98 still shows the crosshatch marks just as in your photo. It's not surprising either way.
Mind you, I am not talking 5W-30 all the time. I'm talking winter use.

You are still saying that GM doesn't recommend 5W-30 oil until 2000? Did you not read what I said about what the 1995 service manual recommends?

Have you ever tried to use a car in less than optimal conditions (such as factory testing) in continuous weather well below 0 F?
I can't count the number of times I've had to spend a good day trying to thaw out a car with 10W- whatever oil in it. They don't always start. In my days of snow plowing I had two older Dodge Power Wagons and a Jeep Wagoneer with a AMC 327 engine.
All had block heaters (tank heater type on all) to ensure they would start. I didn't use 5W-30 in those engines, I had 10W-40 in them.
But that's still a 10 weight oil in a 0 or below degree environment. But at 240 degrees F, the 5W-30 is a 30 weight oil, the 10W-30 is a 30 weight oil and the 10W-40 is a 40 weight oil. Those ancient (1948 and 1950) Power Wagon's liked the 40 weight oil better.

I recall the time I went to the local high school to get my wife's then 1982 Olds wagon with a 455/turbo 400 combo in it started on a cold day when my daughter got out of school. No amount of jumping, charging from a generator, etc. would coax it into running. I rope-towed it to my shop and thawed it out over night before it would start. It was too stiff to crank fast enough to be able to fire.

I haven't a clue what you mean about EPA having something to say about 10W-30 vs 5W-30. You have me there. But it is a fact that lighter oils allow the engine to produce more horsepower. Less drag. Racers know this, and use 0 type oils. If that is true, then a 5W-30 will, on the highway, produce better fuel economy. Maybe that's what the EPA likes.
Also, have you ever been to a seminar on motor oils? If so, you would have learned that a 5W-30 synthetic has a better film strength than a 10W-30 mineral base oil.

So, since you aren't trying to convince me on what oil to use, I assume you won't keep on telling me why 10W-30 is better?
I think it is either just fine, or better than 5W-30 in summer. But not for winter starting. That's all there is to it. I don't care what someone said about a few tests up in northern Saskatchawan or wherever, in the real world an old beater doesn't always like to start when it's 35 degrees below zero. And in my world, a 14 year old car with 200,000 miles on it and little to no care other than a oil change twice a year, cannot be counted on to start in that kind of weather. I will take the advantage the 5 weight oil gives me.


One more thing - If, as you seem to insinuate, a 5 weight oil is hard on the engine, I frankly don't care. I want it to start. I want to have faith that it will start. But I disagree that it's hard on the engine. I say it is not at all hard on the engine. Hard on the engine is trying to get it running when it can't crank. Forcing it, flooding it, getting cylinder walls drenced in fuel thus washing them dry, finally either the starter succumbs to the stress or it might start. Or it might not. If it doesn't start, now it's a tow to somewhere where it has to be thawed out. It happens all the time, thousands of times a day in true cold weather. I don't like being a part of that. I have been, and have learned to do what it takes to ensure the car will start.

Up in Alaska, they used to drain the oil out of the airplanes and keep it inside by the heater or stove to be sure they could start the thing in the morning. Even with the invention of the Tanus heater, sometimes they still do. Similar was done with cars. I've heard of people just running their cars 24/7 up there so they can use it in the morning.
Around here, people use block heaters, less often these days with engines that are truly not as difficult to get running than back in the day. But there still a lot of people using heaters. They used to build charcoal fires under the engine, lay blankets over the engine to insulate it. Another option was to go out and run it for a half hour every 4 to 6 hours.
I'm frankly tired of that stuff, and when I found out what a 5W30 oil can do to aid in cold starting, I took to it like a duck to water. That '98 I've been discussing in this thread started every morning last winter, even when it was 38 below. That's all the colder it got last winter here, but that is pretty cold for an engine. It cranked pretty slowly, and I had that UH-OH! feeling, but it fired and sort of ran, until it warmed a bit. Then it ran fine. If I'd had a 10 weight oil in it, I don't think it would have started. I'm sure it wouldn't have started.

Mark D.

Ranger
12-10-11, 11:37 PM
Have you ever tried to use a car in less than optimal conditions (such as factory testing) in continuous weather well below 0 F?
I can't count the number of times I've had to spend a good day trying to thaw out a car with 10W- whatever oil in it. They don't always start.
Yup, I have started them at -27F with 10W30 after sitting in the parking lot all night long after working a night shift (no block heater, but well tuned).


I haven't a clue what you mean about EPA having something to say about 10W-30 vs 5W-30. You have me there. But it is a fact that lighter oils allow the engine to produce more horsepower. Less drag. Racers know this, and use 0 type oils. If that is true, then a 5W-30 will, on the highway, produce better fuel economy. Maybe that's what the EPA likes.
My point exactly and a good point to ponder. 5W oils Do produce slightly better mileage, BUT you need sophisticated equipment to measure it, as it is so miniscule. THAT is the reason 5W oils exist. The EPA wants them and the EPA has but one agenda and engine protection or longevity is not on that list. The EPA speaks and GM listens. The response may not necessarily be in your or my best interest. The proof is the reduction we are seeing in the ZDDP in todays oils (mandated by the EPA), which may well be reason for this thread in the first place (cam wear). Sometimes you have to read between the lines and draw your own conclusions about manufacturer recommendations.

Mark D
12-13-11, 01:15 PM
So then am I to understand that the EPA mandated 5W-X oils way back over three decades ago for a small improvement in fuel economy? Most people use it to get their car running. Yes, you might have got yours running in -27, but you really wouldn't want to depend on that month after month. A lot depends on how long the car has been sitting.

Well, the cams are out being re-ground. The profile will see a slight change that will basically be a slightly longer duration and slightly lower lift. This should lower the wear factor to the point where I shouldn't have to worry about oil or additives for the remaining life of the car. I probably wouldn't have to worry about it anyway.

I should have the cams back in about a week, maybe week and a half. Meanwhile, as soon as I get my parts in, I'll start reassembly. I've test fitted the heads, they fit over the studs perfectly. I was a bit worried about that and did the best I could to ensure I drilled straight, but was still worried. Nothing to worry about. It all came out just fine. As soon as I have gaskets, it goes together.
While I'm at it, I'm replacing the alternator. Water cooled, not a cheap item. But I got a reman for about 180 bucks. It isn't an easy thing to change out with the engine in the car, and the one that has been there is original with 200 K on it (198 K really) When I spin it by hand, it feels like the bearings are getting a bit long in the tooth. The alternator itself is just a ball of white crust from salt damage. The copper windings are showing a lot of green, again from salt corrosion. It won't be long before a winding shorts.
I've never had great faith in rebuilt alternators, but I'd put my money on a rebuilt before I'd put it on the one that's been in there since forever.
Mark D.

Submariner409
12-13-11, 01:53 PM
:jedi:

Mark D
12-14-11, 11:29 AM
:jedi:

Right on. That discussion isn't going to go anywhere.
Mark D.

tateos
12-14-11, 01:50 PM
I'm with Mark D on this one. I had my second '94 Eldo up in Vermont one time - just North of Burlington, on the way to Montreal. i think it was something like 20 below zero F. I checked the oil level, and it was a little low, so I had a bottle of 10W-30 that I tried to add - it didn't really pour out - it came out sort of like grease - whitish. I took the oil bottle into the hotel room and ran it under hot water to get it warmed up enough to flow. I have to admit I started the car and it worked...and the engine did not fail...but I didn't keep that car too long, so I don't know what the long term life of an engine living in those conditions would be. Here in Phoenix, where we live now, winters are very mild - usually not even a hard frost - but if I were living where temperatures fall below zero, I would not hesitate to use 5W-30 or even 0W-30 oil in a pre 2000 N*

Also, when I was growing up in the Boston area in the 60s, multigrade oils were a relatively new thing, and some people still ran single weight oils - we ran 10W in the winter, and 30 weight in the summer. I don't remember anyone using 20 weight

mtflight
01-11-12, 03:56 AM
casual use of engine oil additives (especially the ZDDP concentrates) runs the very real possibility of permanently damaging the catalytic converter.

I started using the stuff Ranger mentioned earlier (below) as of my last oil change. The instructions state 1 bottle for every 5 qt of oil bring ZDDP levels to what they were when these Northstars were designed (SF?). I only added 1 bottle. I don't think they will cause catastrophic catalytic converter failure if used following these directions. If I understand correctly the newer converters are more sensitive to ZDDP, perhaps because they aren't as robust (cost cutting) yet the EPA requires they be guaranteed to survive to 100K miles--the force behind the reduction in ZDDP.

Has anyone done oil testing after the OLM expires with the current oils? My understanding is that ZDDP is depleted gradually, thus sooner oil changes would also help with the ZDDP "deficiency" for those of us with the pre 2000.




This stuff? ZDDPLUS

http://www.zddplus.com/imgs/zddplus_4oz.gif

RippyPartsDept
01-11-12, 09:12 AM
someone with a newer DTS (superjim maybe) has sent some samples out to blackstone labs after his OLM hit 0%
i think he said that they told him he could extend his interval by a few thousands miles and still be safe
he's using mobil1 and getting well over 10,000mi per oil change

Submariner409
01-11-12, 10:10 AM
I did three Blackstone Labs oil analyses in the 1.5 years after buying the car. This was on SL and SM Pennzoil Platinum 5W-30 synthetic. At the time the oil/filter change interval was in March and October, mileage notwithstanding (4,500, maybe). The analyses said that I could radically extend my change intervals, given that the car sees a lot of long highway driving and minimal in-town stop&go. (Engine guts get far less wear on the highway than in town driving.) The car still uses Pennzoil 5W-30, WIX filters, gets over 4,500 miles a quart, and now I do the oil/filter change in March - once a year - and that's at about 7,000 - 9,000 miles. I currently use 6.5 quarts of Platinum 5W-30 and one quart of Platinum EURO 5W-40 with a WIX 51522 filter.

You could take a look at Joe Gibbs Racing and pick up a case of his 10W-30 HR synthetic - it has a high ZDDP load, but one quart mixed with whatever you're running now would not affect viscosity enough to matter - you would get a ZDDP boost, though.

API oil specification:
SH - 1993
SJ - 1996
SL - 2001
SM - late 2004
SN - ~2009/2010

Oddball picture - but here's a shot of the truck air filter, engine oil stabilizer (long-term layup) and a Blackstone sample bottle.

drewsdeville
01-11-12, 10:34 AM
I can believe how some of you guys can turn a simple activity like an oil change into an ulcer producing science experiment. Just keep the oil clean and drive the vehicle. The rest of the world is managing - I can't remember the last time I saw a modern, properly maintained engine (even high performance) with bearing knock or lifter noise, and that's all without the nonsense in the picture above. If the Northstar is chewing cams with proper maintenance, the problem lies in the design, metallurgy, improper hardening, etc. Nothing you dump into the crankcase can fix any of it.

Interesting that the general consensus is against cooling system additives, using standard conventional coolant changed at the manufacter specified interval, but this thread shows that you all love the special oils, stablizers, detergents, and other crankcase additives. Go figure.

Post #31 is the most informative post in this thread. Change your oil, drive, and be happy. If a problem occurs, it's not because you didn't use enough additives or "special" oil - it's because no machine is perfect, and s*** happens

Submariner409
01-11-12, 06:01 PM
without the nonsense in the picture above

For someone who does not understand engines and their maintenance, care and proper preventative maintenance may well seem to be nonsense............but for someone who builds various forms of heavy duty engines as a hobby and business, the care and feeding of those engines and the oil ("blood") they circulate is of prime importance. Oil analysis is a very old and proven method of preventative maintenance, used by every sort of commercial, marine, racing and aircraft engine manufacturer for many, many years. Oil stabilizers (NOT Lucas "stabilizer") have been used by fleet and military maintenance depots since WW-II: They're a good preservative solution for engines that sit for more than a couple of weeks.

Most automobile owners never even bother to read the owner's manual, much less join an enthusiasts Forum - the ones who come here to contribute and learn are what keeps hobbyists and true gearheads interested in their toys.

mtflight
01-11-12, 07:50 PM
I can believe how some of you guys can turn a simple activity like an oil change into an ulcer producing science experiment. Just keep the oil clean and drive the vehicle. The rest of the world is managing - I can't remember the last time I saw a modern, properly maintained engine (even high performance) with bearing knock or lifter noise, and that's all without the nonsense in the picture above. If the Northstar is chewing cams with proper maintenance, the problem lies in the design, metallurgy, improper hardening, etc. Nothing you dump into the crankcase can fix any of it.

Interesting that the general consensus is against cooling system additives, using standard conventional coolant changed at the manufacter specified interval, but this thread shows that you all love the special oils, stablizers, detergents, and other crankcase additives. Go figure.

Post #31 is the most informative post in this thread. Change your oil, drive, and be happy. If a problem occurs, it's not because you didn't use enough additives or "special" oil - it's because no machine is perfect, and s*** happens

Sorry, and no offense but from your post it seems you have no idea what we are talking about. This information pertains to flat tappet engines (in this case 93-99 Northstar only). It's great that you're free to post your opinion, but in this case it was of little or no value. Please don't take it personal. I do respect your opinion but it doesn't hold a candle to reality in the specific conversation you pitched into. The situation is that the oil zinc levels were higher when the engines were designed. These are critical in metal to metal contact and rubbing points. In 2000 the Northstar was upgraded to roller finger followers instead of flat tappets so no more rubbing metal and no need for the extra zinc. That's the issue.

http://www.hotrod.com/techarticles/engine/flat_tappet_cam_tech/viewall.html

----------


someone with a newer DTS (superjim maybe) has sent some samples out to blackstone labs after his OLM hit 0%
i think he said that they told him he could extend his interval by a few thousands miles and still be safe
he's using mobil1 and getting well over 10,000mi per oil change

This is pretty cool, but the ZDDP deficiency is more critical for the flat tappet Northstars up until 1999.

drewsdeville
01-12-12, 12:32 AM
For someone who does not understand engines and their maintenance, care and proper preventative maintenance may well seem to be nonsense............


Not exactly. There's a difference between simple preventative maintenance and over-analysis. The definitions between these two terms can vary depending on what's at stake. While cars are expensive enough that many people understand the importance of caring for them, they are also cheap enough that people don't have the time or resources to devote to problems that aren't there, which is what this discussion is. Many times, it's best just to worry about problems as they present themselves rather than anticipate them and seek them out. You seem to understand this - you relay nearly the same speech in every headgasket thread.

That said, none of us are in high risk situations like the commercial and industrial applications you've mentioned. Far from the same scenario we are discussing here, which is typical John Doe in his home driveway.

Pertaining to this discussion, I just don't see how the benefits outweigh the the costs. After all of the time and money spent studying drain oil and purchasing expensive oil and additives, one could probably happily drive the vehicle worry free, and just replace wiped cams IF/when they ever caused a problem.

----------


The situation is that the oil zinc levels were higher when the engines were designed. These are critical in metal to metal contact and rubbing points. In 2000 the Northstar was upgraded to roller finger followers instead of flat tappets so no more rubbing metal and no need for the extra zinc. That's the issue.

I understand.

You do realize that there are millions of other flat tappet engines still roaming the streets, don't you? As we speak, I have a 1989 4.5 Eldorado in my driveway. Flat tappet engine, filled with off-brand conventional 10w-30. Always has been. Do you find it to be an act of God that this engine purrs nearly silently with good, strong power and nearly 210k on the clock? Is the oil change I just gave it going to kill it? What about my 1966 poly 318 that still gets filled with conventional and an old canister-style oil filter? Should the cam lobes have ended up in the drain oil long ago? After all, it wasn't designed for this new-fangled oil that we have 50 years later. :hmm:

mtflight
01-12-12, 02:32 AM
Good arguments but adding zinc is cheap. I put standard 10w30 in it and add the zddp for another $10 which goes a good 5000+ miles per the OLM. My 98 had cam lobe wear and it made a little almost unperceivable noise.

Submariner409
01-12-12, 08:53 AM
The bottom line is that every car owner in here - or in any other brand forum - has his/her experience, standards and prejudices on car and engine maintenance. This thread was started to address possible sources, prevention, and repair of flat tappet camshaft wear. To preach to only one level of owner knowledge, as drewsdeville preaches to the lowest common denominator (by his own admission), is to deny the more cautious, analytical (and, yes: fanatic) owner the benefit of the knowledge of others.

There is a staggering amount of experience and advice in the first 5/6 of this thread, and everyone would be well served to go back and review it: You read it all, digest the varying advice, and use what your situation warrants, but to stick your head in the sand and reply that extra measures are not necessary or desirable is counter to education or even good mechanical theory.

With that, I am out of yet another oil war.

RippyPartsDept
01-12-12, 10:15 AM
This is pretty cool, but the ZDDP deficiency is more critical for the flat tappet Northstars up until 1999.

Yeah, i've got a '99 so I'm fully aware of the lifter/cam wear ... I hear it actually

tateos
01-13-12, 06:46 PM
I kind of thought the idea of the GM OLM is to make oil analysis unnecessary in most cases...no?

I also don't think there's anything wrong with adding something to fluids, or changing drain/refill procedures or intervals, in an effort to avoid premature failure and replacement/repair of components that time and experience have shown to be trouble prone. For example:

Northstar engines (ALL years, some years more than others - my opinion) are more prone to HG failure than average...so it can't hurt to change the coolant more often than the factory recommended 5 years/150K miles.

Flat tappet high mileage (100K+ miles) Northstar engines are prone to excess exhaust cam lobe wear - it probably can't hurt to add a little ZDDP during oil changes.

Mark D
01-24-12, 05:43 PM
Well, in my case I had the exhaust cams ground to a new profile that should allow me to run the car without worrying about zinc OR cam wear.
Drew.... should realize that lots of flat tappet engines work just fine in the zinc free environment. Cam profile plays a larg part of this. That is, in my opinion, a large reason why there is much less of a problem with the intake cams on a Northstar engine than the exhaust cams.
Though they were reground by a reputable shop, I still used oil with decent zinc and Lunati's engine break-in additive for the first oil.
After that, I'm going back to just the typical oil. I'm sure it'll last the life of the car.
I've been doing some work on a well worn and heavily ignored '94 STS for a lady who bought it that way. I can hear those cams slapping against lifters and I can see in my own mind just what they look like. She can't afford to do anything about it, so I'm not suggesting anything. It'll run for quite a while just as it is, but it really isn't right. If I owned the car, It would be apart getting the cams redone.

By the way, the Northstar engine actually switched to roller cams in a mid-year switch during the 2000 production run. Some 2000 cars are still flat tappet. I believe this information to be correct. It comes from a friend who is GM trained Cadillac - Northstar. He's done dozens of head gasket repairs. If this is incorrect information, I would like to know that too, but I believe it to be correct.
Mark D.

RippyPartsDept
01-24-12, 07:22 PM
I think you heard correctly about the mid year switch in 2000. If you want me to ask around the shop to get corroboration I'll gladly do it.

Also, wrt my '99 with flat tappets would you also recommend doing nothing if they only make noise when it's really cold (until the oil warms up a bit)?

tateos
01-24-12, 08:35 PM
My father bought a 2000 Deville DTS right when they first came out - I want to say it was in 1/2000...or was it 1/1999 - anyway, it had the new style engine. I seem to remember that the 2000 Deville was the first Cadillac body style to get that engine...but maybe there were other body styles (Seville/Eldorado) that had 2000 models come out with the old style engine

Submariner409
01-25-12, 02:03 PM
There's a LOT more to the 2000 engine redesign than a change to roller cam followers - different crank and reluctor wheel, for one = different ignition system = coil cassettes vice 4 individual coils = very obviously different cam [valve] covers.

If your "2000" model Cadillac FWD was built in "09/99" (driver's door sticker) - just after the beginning of the "2000 model year" - what ignition system does it have ???

maeng9981
01-26-12, 02:09 AM
According to the old GM VIS, mine was built on 01/04/2000. I have the new designed engine with roller cam followers. I am pretty sure all 00+ year model vehicles have the "new design" engine. Only if CompNine was up, I'd go for a search session...

Mark D
01-26-12, 04:36 PM
I think you heard correctly about the mid year switch in 2000. If you want me to ask around the shop to get corroboration I'll gladly do it.

Also, wrt my '99 with flat tappets would you also recommend doing nothing if they only make noise when it's really cold (until the oil warms up a bit)?

My opinions here are my opinions, probably subject to as many other opinions as there are people using this forum. Or maybe a few more. :-)
I don't know what you're hearing when you start it cold, but first of all it could be a bit of piston slap, perhaps caused by a slightly stiff wrist pin.
Otherwise, more likely, you have lifters that are a bit soft and need oil pumped up before they hold well. Or, yes, the cam lobes and buckets are both worn, some more than others if your car follows the norm. If it were my car, and it only clicked a bit when it's cold and then sounds fine, I'd just let it go for now. You aren't likely to do any harm to it, at least not in the short term and maybe not even long term.
Wait until you really know you have to do it. It's not easy and it's not cheap. Maybe, in the end, the engine will outlive the rest of the car anyway. Ya' never know.
Once you get into the cams, you might want to pull the heads and do the valves. On the '98 I just did head gaskets on, it had about 198K on it and the exhaust valves were shot. I replaced with new. Yes, the car would have run for tens of thousands of miles and I'd never have known. But they were all leaky, badly pitted in the margin. So it became 16 new exhaust valves, 16 new lifters, and two re-ground cams. That added up to a few bucks, yes! Intake valves, cams and lifters were fine and got by with a regrind on the valves and seats cut.


Question for anyone who has experience in this -
Is it possible to swap roller cam heads onto an older flat tappet engine? If not, would it be possible to modify an older flat tappet head to roller? I'm not planning to do this any time soon, but just wondering for future reference.
Mark D.

RippyPartsDept
01-26-12, 04:48 PM
that's kind of what i was thinking - don't worry about it

but you did have some ideas i didn't think of (piston slap, etc)

thanks mark :thumbsup:

Submariner409
01-26-12, 05:10 PM
My opinions here are my opinions,

Question for anyone who has experience in this -
Is it possible to swap roller cam heads onto an older flat tappet engine? If not, would it be possible to modify an older flat tappet head to roller? I'm not planning to do this any time soon, but just wondering for future reference.
Mark D.

The opinion paragraph was good - all good.

^^^ No to both alternatives. No aftermarket cam and follower support is only the tip of the iceberg.

RippyPartsDept
01-26-12, 06:03 PM
yeah, i asked around and there's just no way to do it ... the heads are too different (especially in the are of the cross-over)

eldoedwardo
03-26-12, 04:25 PM
Hello everyone, I hope happy days ahead for you.
This is a great forum with 99% of it based on factual information, years of knowledge, great people willing to share and (bonus)its free!
I had an exhaust cam breakdown and opted for an upper rebuild,costly but quite effective 20k ago, no known reason for it ,but the heat on the valves sounds logical.
Mark D. my opinion is that you were alittle harsh, almost argumentative with my forum friends . We do this to relax and learn, please lighten up a tad.You will gather more information this way. I know loaning your ride out can be frustrating,please check it in while at the forum.
Thanks everyone for all the info.......Ed