: Help, still overheating after headgasket job .



ramairetransam1985
09-11-07, 04:22 PM
hi ive been a memeber here for a little while but lurked for months . Well i have a 2000 base deville and i love it . But i developed an overheating problem one day after i washed the engine and then got the car washed . About 10 min after i got out of the car wash it overheated . I thought i just got a sensor wet but not the case. I had a blown headgasket and after a lot of thinking i decided to go through with it . I had a gm dealer do it who has done about 6-10 other headgasket jobs on the n*. Well they did the head gasket and it still overheated . They didnt magnaflux the heads or block but check the heads for being flat and i guess were fine. Well they thought they had air in the system or maybe they did . But they tried things and still over heating . SO they check further and found the waterpump to be weaping and they said we will fix that and that must be where the air is coming in . Welp they changed it and same thing . So out of ideas they had the radiator flushed thursday , and installed it friday . They got some crap out of it but nothing the guy who flushed it thought it would cause a car to overheat. O and btw the week before when they gave it back to us since they thought they fixed it they let it sit and run for 3 hrs and no overheating . and then that night after we paid for it it overheated. So up to current they radiator they run it saturday and its fine and then monday morning and its fine , monday afternoon it overheats again .

Now this car has been checked for compression and it passes. it also passes the coolant leakdown test too . And they also analyzed the exhaust and no water it in. Normal reading . SO now they are stumped and like want me to tell them what to do with it . when i had this done they said they warrantee it for 12 months or 12000 miles. And i allready paid for it .

so has anyone else had this many probs with it . now i also cant believe that the car would crack a head or something since these cars have camel mode and can run with no coolant in them . But do you guys think its a crakced head or air still in the system .

I mean it can run for hrs idle and not overheat but then overheat when driving . Im sorry if i missed anything but this makes me mad this subject since ive allready spend 2500 and havent had my car for over a month and a half.

So what should i do , anyone ever heard of this many probs.

misfit6794
09-11-07, 08:19 PM
That is a very strange situation, very strange.

It may sound dumb but did they do both headgaskets? ANother member had a caddy dealer only replace one of the headgaskets, only to have to tear the motor down a second time to do the other.

Second question is did they timesert the block when they repaired the headgaskets? THe reason most n* headgaskets fail is because the headbolt threads pull out of the block. The timesert kit replaces the threads with bigger ones that won't back out. I know they did the tests for a headgasket but its possible that when they torqued done the head the bolts backed out since the threads were bad. Find out from the dealer exactly what they did with the threads in the block.

Other than that maybe a bad thermostat? Or something more serious like a warped head or cracked. You will be suprised at how much stuff a dealer lets slip by. It may be time for a second opinion. Just very strange.

AJxtcman
09-11-07, 09:23 PM
That is a very strange situation, very strange.

My first question is did they timesert the block when they repaired the headgaskets? THe reason most n* headgaskets fail is because the headbolt threads pull out of the block. The timesert kit replaces the threads with bigger ones that won't back out. I know they did the tests for a headgasket but its possible that when they torqued done the head the bolts backed out since the threads were bad. Find out from the dealer exactly what they did with the threads in the block.

Other than that maybe a bad thermostat? Or something more serious like a warped head or cracked. You will be suprised at how much stuff a dealer lets slip by. It may be time for a second opinion. Just very strange.


You have NO clue on what a TIMESERT IS!!!!!
I am not impressed by Timesert Insterts for Northstar head bolts!
I have installed a hundred or so, but I have installed them all but 1 on 99 and prior blocks. I have passed on several block that would never hold a Timesert. The block are just too badly deteriorated on the 99 and prior to hold Timesert inserts MOST of the times.
A Timesert insert just makes the bolt bigger. It is not a permanent part of the block. You put the little piece of crap in the block. Then you heat the block and it expands leaving the insert loose. Just like if you heat a rusted nut.


Pitted 99 block Before cleaning
35389
.

Pick in a hole after it has been drilled for a timesert
35390
.

Pit after hole has been drilled
35392
35391


hi ive been a memeber here for a little while but lurked for months . Well i have a 2000 base deville and i love it . But i developed an overheating problem one day after i washed the engine and then got the car washed . About 10 min after i got out of the car wash it overheated . I thought i just got a sensor wet but not the case. I had a blown headgasket and after a lot of thinking i decided to go through with it . I had a gm dealer do it who has done about 6-10 other headgasket jobs on the n*. Well they did the head gasket and it still overheated . They didnt magnaflux the heads or block but check the heads for being flat and i guess were fine. Well they thought they had air in the system or maybe they did . But they tried things and still over heating . SO they check further and found the waterpump to be weaping and they said we will fix that and that must be where the air is coming in . Welp they changed it and same thing . So out of ideas they had the radiator flushed thursday , and installed it friday . They got some crap out of it but nothing the guy who flushed it thought it would cause a car to overheat. O and btw the week before when they gave it back to us since they thought they fixed it they let it sit and run for 3 hrs and no overheating . and then that night after we paid for it it overheated. So up to current they radiator they run it saturday and its fine and then monday morning and its fine , monday afternoon it overheats again .

Now this car has been checked for compression and it passes. it also passes the coolant leakdown test too . And they also analyzed the exhaust and no water it in. Normal reading . SO now they are stumped and like want me to tell them what to do with it . when i had this done they said they warrantee it for 12 months or 12000 miles. And i allready paid for it .

so has anyone else had this many probs with it . now i also cant believe that the car would crack a head or something since these cars have camel mode and can run with no coolant in them . But do you guys think its a crakced head or air still in the system .

I mean it can run for hrs idle and not overheat but then overheat when driving . Im sorry if i missed anything but this makes me mad this subject since ive allready spend 2500 and havent had my car for over a month and a half.

So what should i do , anyone ever heard of this many probs.

I have never seen a cracked head.
Find out if the dealer is using this tool Vac-N-Fill (GE-47716)
This is a required tool and they must have it. They may not have used it, but they should use it on a Northstar.

If they use this tool and remove all the air from the system with this tool and then the air come back it has a Combustion Camber leak into the cooling system!
.
Tool info http://216.182.211.32/techlink/images/issues/feb06/TLFeb06e.html#story1

.
.
It is possible that they did not clean the head bolt holes properly and stack the sealer. This will cause the threads to break out of the block. Also the block has an air dam built at the top of the cylinder liners. It protects the the head gasket. The dealer may have removed it by mistake.
Air dam
35388

zonie77
09-12-07, 11:47 AM
Is it losing coolant?

Does it overheat in every driving situation or only at certain times? Hills/mountains, heavy traffic, cruising on flat highway,suburban driving?

Stop at a radiator shop and have them do an exhaust gas test on the coolant.

ramairetransam1985
09-12-07, 12:47 PM
they did both headgaskets and they did not use timecerts . They said they have done some and not all of them needed it .

My father and i went up last night to talk with them and they are gonna take the engine back out and send the heads out to check them , get them magna fluxed .

? why would they need to timecert the block if all the bolts torque down ? Wont it be fine .

It isnt loosing coolant either it usually overheats when they get to a hill or something but it doesnt cool down . I just dont understand how it could eb fine for like a day or two and then screw up .

they also replaced the thermostat , and the surge tank cap .

misfit6794
09-12-07, 12:55 PM
Really sounds like a shoddy repair, especially since every other part of the cooling system has been replaced and you are still experiencing problems. You may be better off cutting your losses and replacing the engine or wait till the dealer gets the headgaskets repaired correctly. Although its weird that it isn't losing coolant.

AJxtcman
09-12-07, 02:49 PM
Really sounds like a shoddy repair, especially since every other part of the cooling system has been replaced and you are still experiencing problems. You may be better off cutting your losses and replacing the engine or wait till the dealer gets the headgaskets repaired correctly. Although its weird that it isn't losing coolant.

This is an 00 not a 99 and prior. The material used in the block casting was redisigned for 00. It has a better blend. I have not seen an 00+ that could not take a Timesert.

dkozloski
09-12-07, 03:07 PM
they did both headgaskets and they did not use timecerts . They said they have done some and not all of them needed it .

My father and i went up last night to talk with them and they are gonna take the engine back out and send the heads out to check them , get them magna fluxed .

? why would they need to timecert the block if all the bolts torque down ? Wont it be fine .

It isnt loosing coolant either it usually overheats when they get to a hill or something but it doesnt cool down . I just dont understand how it could eb fine for like a day or two and then screw up .

they also replaced the thermostat , and the surge tank cap .
Magna Flux inspection involves magnetizing the part to be inspected and covering it with a petroleum solution containing fine magnetic particles which are attracted to the magnetic field disruption caused by a crack. The cylinder heads are made from aluminum and are non-magnetic. Somebody there is full of crap. Crack inspection of aluminum alloy parts involves cleaning the part and applying a dye penetrant solution which is then rinsed off. A dry powder is applied to the part which draws the dye from a crack showing the location of the crack. Things don't sound very good about the shop that is doing your work. If what you have told us is accurate they are totally unqualified.

Ranger
09-12-07, 05:30 PM
they did both head gaskets and they did not use timecerts .
It isnt loosing coolant either it usually overheats when they get to a hill
It's the head gaskets. If they had Timeserted all 20, you would not be having this problem. Kind of add to Koz's statement. They are unqualified.

misfit6794
09-12-07, 08:12 PM
Thats what I thought also ranger, although ajxtcman seems to think I'm crazy.

blb
09-12-07, 10:01 PM
Agreed, the dealer should have timeserted the block. Of course, if the factory timeserted the blocks to begin with, the Northstars wouldn't have the terrible reputation for unreliability they have earned, and GM wouldn't have lost so many loyal customers.

Murphyg
09-12-07, 10:32 PM
Agreed, the dealer should have timeserted the block. Of course, if the factory timeserted the blocks to begin with, the Northstars wouldn't have the terrible reputation for unreliability they have earned, and GM wouldn't have lost so many loyal customers.
How terrible "Really" is the reputation. When it comes down to it the N# is one fine engine.

97Concours1
09-13-07, 03:26 PM
... Of course, if the factory timeserted the blocks to begin with, the Northstars wouldn't have the terrible reputation for unreliability they have earned, and GM wouldn't have lost so many loyal customers.

This would be a good topic for a new thread. I'll bet a cost-benefit analysis was done and someone got a promotion for the cost savings of NOT using inserts at the factory. This is the problem with the domestic auto-makers; short-term thinking. Iím sure the failing head gaskets are doing more damage to customer loyalty than can be accurately measured. The word gets around at the golf courses and country clubs.

misfit6794
09-13-07, 05:30 PM
Its got a lot to do with the headbolts pulling out. But my mechanic thinks its that gm/cadillac used a very cheap aluminum (hence too soft) for the engine block. I am not sure how much truth there is to it, but it would make sense.

Ranger
09-13-07, 07:01 PM
Its got a lot to do with the headbolts pulling out. But my mechanic thinks its that gm/cadillac used a very cheap aluminum (hence too soft) for the engine block. I am not sure how much truth there is to it, but it would make sense.

AJ has eluded to that. I believe he said the 2000+ are better.

zonie77
09-13-07, 09:13 PM
I would say they did not have to timesert the engine at the factory, but adding larger/longer bolts and stressing the coolant change at 5 years probably would have eliminated 90% of the HG problems.

97Concours1
09-14-07, 01:16 PM
Those poor little aluminum threads never stood a chance. They are just overstressed. They are only about 7/16 inch diameter and pretty fine. The bolts are grade 8+ hardened steel and torqued to over 95 lb-ft! It really became clear to me when I torqued my head bolts down. I had a two foot long torque wrench and was busting a nut getting to the required angle. I just kept thinking that there is no way aluminum threads could ever handle this (I had just installed the Norm's "boat anchor" inserts so I wasn't worried.)

stoveguyy
09-14-07, 02:33 PM
i see the torque procedure is 22 ft/lbs than 60-60-60 degrees. where did you come up with the 95ft/lbs value?

racerxnet
09-14-07, 04:36 PM
I would not waste my time with the current shop, nor with the current head bolts from GM. As the bolts do work from GM, a better solution is to insert all 20 holes with Norms inserts and use the ARP stud kit for Audi/Volkswagon. Your torque value is 65ft lbs for aluminum heads.

Gm techs can whine all they want, but the results when done as suggested, are less prone to repeat failure. You can look up my prior write up on this subject.


MAK

AJxtcman
09-14-07, 08:00 PM
Those poor little aluminum threads never stood a chance. They are just overstressed. They are only about 7/16 inch diameter and pretty fine. The bolts are grade 8+ hardened steel and torqued to over 95 lb-ft! It really became clear to me when I torqued my head bolts down. I had a two foot long torque wrench and was busting a nut getting to the required angle. I just kept thinking that there is no way aluminum threads could ever handle this (I had just installed the Norm's "boat anchor" inserts so I wasn't worried.)

I like his inserts. I just have used them both and can see the best of both worlds. On a 99 and prior norms is the best way to go. I wish the tooling was more like timeserts.

2of8meng@cox.net
09-14-07, 09:51 PM
:thumbsup: I know EXACTLY what you are saying. I did some research because I was at my wits end, too. I found this stuff, (Relatively New) that has been out for only about 3 years. It's called HEAL-A-SEAL. I just couldn't see spending a lot of money that we don't have to throw into this D--M Northstar Engine. Sure they say they are a great engine but that's when they are working the way they are expected to for being a CADILLAC.Anyway this HEAL-A-SEAL Stuff . My mechanic and my husband were trying to decide who was going to hold the dynamite and who was going to light it.:yup:. My husband wanted to go the traditional way, big I don't have the finances nor does he. My mechanic says it would save him time, which he is an excellant mechanic, and doesn't have time to chase him tail or watch someone else chase theirs and also would save us the money we don't have. So I ordered this HEAL-A-SEAL and overnight-ed it to my mechanic. He put it in as directed. I ran it hard for 2 days and brought it back to him for the weekend so he could complete the job by removing the Heal-A-Seal fluid from the radiator, flushing it a few times and putting fresh antifreeze in. We've been driving the car all over for more than a week now and it's like a breath of fresh air to get in and go and not have to wonder if I have my AAA card with me. This is a BIG THUMBS UP FOR HEAL-A-SEAL. Go to www.heal-a-seal.com or call (1-877 - 256 - 9349) EXT. 4 and talk to MR. C. He said his name is too long to pronounce. Tell him Sharon from Connecticut wanted you to call. Good luck, actually no luck needed. Enjoy your CADILLAC.

Ranger
09-14-07, 10:11 PM
I hate to be the one to break the bad news Sharon. Enjoy the fresh air while it lasts, but it is only a temporary fix and will fail in due time. Repairs aka miracles in a bottle DO NOT work. There is only one way to repair a faulty head gasket. Do a search for Thermosgasket by Rfishing.

97Concours1
09-15-07, 03:26 AM
i see the torque procedure is 22 ft/lbs than 60-60-60 degrees. where did you come up with the 95ft/lbs value?

Yes, the torque procedure is 22ft/lbs, then 60-60-60 degrees. (although it has been revised to 30ft/lbs, then 70-60-60 degrees.)

The 95 ft/lb is not a specification. It's just the value that I observed when doing the Torque-Angle procedure above. I used a "click" type torque wrench and set it to 95lb/ft. When I was doing the last 60 degree turn of the procedure, the torque wrench would click shortly before I got to the 60 degree mark(most of the time). The angle is what's important, not the torque.

ramairetransam1985
09-15-07, 07:24 AM
well i called it magnafluxing , i thought they could do it on aluminum heads beacause they would just try and pull a magnatized solution and it would flow to the crack , my bad on that one. What are these boat anchor certs by chuck norris. and then using arp bolts. DO you think i should tell the shop to do the timecerts . They are taking the engine out for free again and now they are gonna check the heads. U havent heard back from them and i went there tuesday or wed . SO i dont know what i should do ,im allready 2200 into this . I dont know it if i should say timesert it anyway or let them do what they do and then when it fails again its their shit. But then again i could be in cape cod 400 miles away from home when it happens and my aaa wont pick it up for free then .


Also do you guys think it was headgaskets since it would sit there and idle for hours with no overheating and then overheat when driven . I mean water pump done, radiator flushed and all flow tested . Im just wondering what the possibility of air being in the system . I m just afraid they are gonna say that the heads are fine and then blame it on the block or some bs . Also are these engine sleeved ????

misfit6794
09-15-07, 11:21 AM
You should definetly have it timeserted so you don't have to go through this a third time, if they would have done it on the first repair you wouldn't be in this situation. I am sure once they get the heads off they'll see the headbolts have pulled.

Ranger
09-15-07, 07:06 PM
Also do you guys think it was headgaskets since it would sit there and idle for hours with no overheating and then overheat when driven . I mean water pump done, radiator flushed and all flow tested . Im just wondering what the possibility of air being in the system .
That's generally how a bad head gasket starts to show itself. The Northstar is self purging, so there should be no air if the purge line is clear.


Also are these engine sleeved ????
Yes. They are cast in place. they cannot be replaced and rarely ever need to be.

97Concours1
09-15-07, 11:42 PM
... What are these boat anchor certs by chuck norris. and then using arp bolts. DO you think i should tell the shop to do the timecerts...

"boat anchor" is a term I used just because the Norm's inserts are much more bulky than the brand name Timesert inserts. Norm is a guy who is making his own version of an insert. They are longer and have a course thread to bite into as much of the soft aluminum as possible. There is a lot of debate that goes on here as to whether inserts should be used, and what version to use. My two cents would be that any time the trouble of removing this engine is undertaked, do everything you can to ensure that you don't have to do it again. To me, this means putting (Norm's) inserts in all 20 head bolt threads. I've only done one head gasket repair. I used these inserts and so far they are working well.

ARP are studs. Instead of bolts, a long "stud" with threads on both ends is threaded into the block head bolt holes. Then the gasket and head is put on. Nuts are then put on the protruding stud ends and tightened. This is a procedure used mostly in racing applications. It has its merits, but is not necessary unless you plan to do something radical with the motor after you get it back together.

AJxtcman
09-15-07, 11:57 PM
"boat anchor" is a term I used just because the Norm's inserts are much more bulky than the brand name Timesert inserts. Norm is a guy who is making his own version of an insert. They are longer and have a course thread to bite into as much of the soft aluminum as possible. There is a lot of debate that goes on here as to whether inserts should be used, and what version to use. My two cents would be that any time the trouble of removing this engine is undertaked, do everything you can to ensure that you don't have to do it again. To me, this means putting (Norm's) inserts in all 20 head bolt threads. I've only done one head gasket repair. I used these inserts and so far they are working well.

ARP are studs. Instead of bolts, a long "stud" with threads on both ends is threaded into the block head bolt holes. Then the gasket and head is put on. Nuts are then put on the protruding stud ends and tightened. This is a procedure used mostly in racing applications. It has its merits, but is not necessary unless you plan to do something radical with the motor after you get it back together.

00+ takes about 45 minutes to have the power train out. They are still cooking hot when they come out.

97Concours1
09-16-07, 12:15 AM
Yes, the torque procedure is 22ft/lbs, then 60-60-60 degrees. (although it has been revised to 30ft/lbs, then 70-60-60 degrees.)

The 95 ft/lb is not a specification. It's just the value that I observed when doing the Torque-Angle procedure above. I used a "click" type torque wrench and set it to 95lb/ft. When I was doing the last 60 degree turn of the procedure, the torque wrench would click shortly before I got to the 60 degree mark(most of the time). The angle is what's important, not the torque.

But, the torque does need to be there too. If, for some reason, the block threads or inserts are failing during the torquing procedure, a low torque value will show on that bolt. You may have turned it to the full 190 degrees, but if the threads are giving, then the bolt will not provide the proper clamp load. This may be why so many head gasket repairs fail. The mechanic turns the bolt to the correct specification, but the clamp load is not there because the threads have failed and he doesn't know it. So, the combination of using an angle gage AND torque wrench when torquing the head bolts may catch a bad one before the whole engine is reassembled.

97Concours1
09-16-07, 12:29 AM
00+ takes about 45 minutes to have the power train out. They are still cooking hot when they come out.

AJxtcman,

You need to see this from the part-time weekend mechanic's perspective. Or, from the guy who is paying to have this work done at $2500-$4000 a crack. It is a huge and expensive undertaking to the rest of us everytime the engine has to come out. Obviously, you have the means and experience to do this with your eyes closed and at no cost. This isn't the case with 99% of the people inquiring on this site.

AJxtcman
09-16-07, 11:38 AM
But, the torque does need to be there too. If, for some reason, the block threads or inserts are failing during the torquing procedure, a low torque value will show on that bolt. You may have turned it to the full 190 degrees, but if the threads are giving, then the bolt will not provide the proper clamp load. This may be why so many head gasket repairs fail. The mechanic turns the bolt to the correct specification, but the clamp load is not there because the threads have failed and he doesn't know it. So, the combination of using an angle gage AND torque wrench when torquing the head bolts may catch a bad one before the whole engine is reassembled.

About 80% of the time they don't reach the 30 ft lb torque. About 10% of the time they go when you are doing the angles. The rest of the time it is an immediate failure. If you look at the picture that I have posted you will see the thread just deteriorate too much.


AJxtcman,

You need to see this from the part-time weekend mechanic's perspective. Or, from the guy who is paying to have this work done at $2500-$4000 a crack. It is a huge and expensive undertaking to the rest of us everytime the engine has to come out. Obviously, you have the means and experience to do this with your eyes closed and at no cost. This isn't the case with 99% of the people inquiring on this site.


I will have to get the picture thing fixed. I have too many posted.
Whet I do the next piston job or what ever on a 00+ I will snap some pictures with time stamps.

Patrick7997
09-18-07, 04:04 PM
AJ, I don't doubt you can do it in 45 minutes....

But then, you have a hoist, lots of tools, a huge shop, air, decent lighting, the right carts.... you have everything.

And there's nothing wrong with that...

However, to us non-pros, trying to do this in our little garage, with no hoist, iffy lighting, less than optimal space... it's a huge job.

I think that was 97 Concours point... it's a big thing to us civilians...

I don't think he was questioning your integrity, or your ability to do it... I think he was just pointing out that to most of us, it's a mammoth undertaking to even think of dropping an engine....

AJxtcman
09-18-07, 08:38 PM
AJ, I don't doubt you can do it in 45 minutes....

But then, you have a hoist, lots of tools, a huge shop, air, decent lighting, the right carts.... you have everything.

And there's nothing wrong with that...

However, to us non-pros, trying to do this in our little garage, with no hoist, iffy lighting, less than optimal space... it's a huge job.

I think that was 97 Concours point... it's a big thing to us civilians...

I don't think he was questioning your integrity, or your ability to do it... I think he was just pointing out that to most of us, it's a mammoth undertaking to even think of dropping an engine....


I would never want to do a 93 tp 99 on the ground.

clarkz71
09-19-07, 12:57 PM
I would never want to do a 93 tp 99 on the ground.


Why ?? Enquiring minds want to know.

ramairetransam1985
09-22-07, 09:41 AM
hey guys good news, i got the car back tuesday or wednesday . They did have to pull the engine again becAUSE THEY WERE AT A LOSS . well when they pulled the engine they had coolant leaking around the back . So they looked at a metal pipe back there and realized it was full or rust and other crap , so they cleaned it out and never did anything with the heads since they were allredy on good. Well the car is running awesome , back to normal . 2200 bucks to fix it , they never charged me for the water pump and never charged me for when they took out the radiator. It was frustrating and it took a while but they took care of me. the only thing i can think of where they got the gunk was from when they flushed the rad and it kicked up some. This pipe wasnt plugged when the did the engine out the first time . So it got in there somehow. So now i have a 12 month 12000 miles warranty . thanks for the help and suggestions . This site has some great info and people.

Ranger
09-22-07, 01:49 PM
The pipes you speak of are heater pipes and are known to rust out and leak for some reason. They are terribly difficult to replace so I hope they replaced them since you said they were leaking.

ramairetransam1985
09-22-07, 02:27 PM
sorry i didnt mean they were leaking , their was coolant coming out of the pipes, which is what alerted them to it . But i dont think they replaced it .

dhm37
09-27-07, 04:48 PM
Interesting thread. I had '98 heads plugged up with "stop-leak" goop (mixed with walnut shells from the BarsLeak tablets. took a while to figure that out and get them opened up again. Used Norm's inserts in the block (had used TimeSerts on a '96, and didn't like them). On second head installation, I lost my place on which 60 degree I was on and easily snapped a head bolt. Those big inserts seem to be quite strong. On the '96, I think a couple of TimeSerts gave way (block threads gave way) just at the last part of the last 60 degree twist. Felt like it, but may never know. Using Norm's inserts in a '97 that I am working on now (with rear main seal questions on another thead.

Isn't this a great forum, or what?