Northstar Headgasket/Bolt Failure? Please let us know

[Ur7x]

Originally Posted by N0DIH

GM could say the same thing, people "abused" their cars by not changing coolant or flooring it, or something I am SURE they could come up with to.

Regarding "flooring it" You need to floor Northstars on a regular (at least once a week) basis....

The other common thing that many North* head gasket failures seem to have in common is the owner says "But I babied it since day one"

I never heard a head gasket victim say "It was only a matter of time... I drover her HARD"

It is generally accepted that "blowing out the carbon" once a week or so while keep these engines running good to 200,000 miles and beyond.

[N0DIH]

I do it in my car at least DAILY, but try to write that into the owners manual or convince Cadillac owners of it.

I wanted to get a N*, but I knew I would be nailing it often, and don't want it "blowing" the gasket on me. I worry on my mom's 97 Deville, she has probably floored it 2x since 1997.... The first time she had to call me to tell me how fun it was!

[Cryptoman]

So if Dex-Cool potentially has problems, what are you folks changing it out with? Any aftermarket coolant certified for aluminum engines?

[jarhead99]

I am new to this forum and have done quite a bit of reading on the head gasket issues and repairs on these vehicles. I test drove a 99 STS and am considering purchasing. This vehicle has had a head gasket problem in the past and am told the current owner who intended on keeping the car decided to have everything done. He had every intention on keeping the car so while they had the motor out for the head gasket repair he had them rebuild the motor. This was not done by GM. He used a reputable shop in NY.

New rings
New pistons
New gaskets
New suspension
New brakes
New calipers
etc.

The current owner has invested over 9k in making the car perfect but is forced to sell due to hardships. Have not seen the receipts yet but am told they will show me all receipts of work that was done. I talked to the shop that rebuilt the motor. There is a 1 year warranty on the motor which leaves 7 months if I purchase the vehicle.

My question is do you think this is a good deal or do you think I would be better off finding a low mileage STS under 100K. The dealer where the car is located swears the car is perfect. Based on your experience with these motors does this sound like a winner or should I run. HELP???

[Ur7x]

Originally Posted by Cryptoman

So if Dex-Cool potentially has problems, what are you folks changing it out with? Any aftermarket coolant certified for aluminum engines?

Look at the results and think about what is going on...If Dexcool was the issue how come (essentially) no headbolt failure in the LS1/2/x camp? They have aluminum blocks and they run Dex too? Also why the sudden drop in head gasket victims after 2000? Those cars have been soaking Dex for about 8 years but there failure rate is fractions of the 97/98/99 cars... less then 1/5th as many or an 80% drop.

What the result show, and something that many of us have suspected for 3 or 4 years now... either GM got some bad gaskets in 97/98/99 or GM cast some bad blocks in 97/98/99 or GM used some bad headbolts or headbolt sealer or headbolt lub in 97/98/99

My opinion, this has little to do with Dex... But I would still change it often. There have been enough gelling "mixed" coolant stories that I would be more afraid to switch to something else then stick with Dex. My 2002 is on its THIRD batch of Dex-cool

[97Concours1]

Originally Posted by jarhead99

I am new to this forum and have done quite a bit of reading on the head gasket issues and repairs on these vehicles. I test drove a 99 STS and am considering purchasing. This vehicle has had a head gasket problem in the past and am told the current owner who intended on keeping the car decided to have everything done. He had every intention on keeping the car so while they had the motor out for the head gasket repair he had them rebuild the motor. This was not done by GM. He used a reputable shop in NY.

New rings
New pistons
New gaskets
New suspension
New brakes
New calipers
etc.

The current owner has invested over 9k in making the car perfect but is forced to sell due to hardships. Have not seen the receipts yet but am told they will show me all receipts of work that was done. I talked to the shop that rebuilt the motor. There is a 1 year warranty on the motor which leaves 7 months if I purchase the vehicle.

My question is do you think this is a good deal or do you think I would be better off finding a low mileage STS under 100K. The dealer where the car is located swears the car is perfect. Based on your experience with these motors does this sound like a winner or should I run. HELP???

Because its only been 3 months, I would be somewhat concerned that the head gasket job didn't hold and they are looking to unload it. Did they use Timeserts or Norm's inserts for all twenty headbolts? I think I would still do an exhaust gases check on the radiator before deciding to purchase it. If all is ok, it would be a great deal to have one with the problems taken care of already.

[jarhead99]

I had this vehicle looked at by a local shop today. The mechanic did not find any error codes in the computer but did find small traces of hydrocarbon in the overflow tank. He said this is an indication of seepage from the head gaskets and recommended adding stop leak to the coolant. After we explained to him that the motor had just been rebuilt he said it is possible that the gaskets have not sealed completely because it was just done and had less than 500 miles on it. Does this sound normal to you?? Or is this an indication that the gaskets did not hold??

I thought the new gaskets were supposed to take care of the problem altogether?? Is there a bonding time required for the gasket to completely adhere and stop any seepage???

Was told timeserts were used.

[MRBENZ]

To Clark71, my personal experiences and what I see on my local area do not support Cadillac as being a well built car. When I buy one Cadillac and it is a piece of crap, which I have spent a third of what it cost me when I bought it to fix a blown head gasket that should have never blown and then I look at not one, but three MB with 90k, 179k, and 220k on the clock and never ( I repeat never) have had a blown headgasket. Then, I say that the odds of getting a cadillac and being able to drive it for many miles without a major dip in the wallet, is very low. MB has their problems like the next brand, but there is one thing that you will not see very often and that is a blown head gasket at 82k. You will never make me believe that Cadillac makes a tight motor that will give many years of performance without the Well Fargo truck following you waiting for the repair.

[99 eldog]

99 eldog 11300 miles so so sad

[clarkz71]

Originally Posted by MRBENZ

To Clark71, my personal experiences and what I see on my local area do not support Cadillac as being a well built car. When I buy one Cadillac and it is a piece of crap, which I have spent a third of what it cost me when I bought it to fix a blown head gasket that should have never blown and then I look at not one, but three MB with 90k, 179k, and 220k on the clock and never ( I repeat never) have had a blown headgasket. .

What year and models are your MB's? I'll tell you what you have or will have to repair/replace on them.

It's funny, this week we have a C280 with a M104 engine coming in for..........................................,
you guessed it, a HEADGASKET.. I'll take some pics and post them while it's apart.

It's pissing oil so bad we had to leave off the splash shield.

On the other hand I've had several Northstar Cadillac's and I never (I repeat never) had a blown headgasket..

As long as people like you have out of warranty Mercedes I'll have a job
as I plan to stay at an independent Mercedes Benz shop rather than go
back to a dealer. 20 years was enough.

[99 eldog]

1999 Eldorado 113000 miles
Well taken care of mint condition. How could this happen?

[97Concours1]

Originally Posted by jarhead99

I had this vehicle looked at by a local shop today. The mechanic did not find any error codes in the computer but did find small traces of hydrocarbon in the overflow tank. He said this is an indication of seepage from the head gaskets and recommended adding stop leak to the coolant. After we explained to him that the motor had just been rebuilt he said it is possible that the gaskets have not sealed completely because it was just done and had less than 500 miles on it. Does this sound normal to you?? Or is this an indication that the gaskets did not hold??

I thought the new gaskets were supposed to take care of the problem altogether?? Is there a bonding time required for the gasket to completely adhere and stop any seepage???

Was told timeserts were used.

Did you buy the car? I don't think head gaskets take time to seal. I think they either seal or leak right from the beginning. From all I've heard, adding sealant doesn't work. If you have to add sealant, I'd be very concerned and would probably not buy the car.

Maybe some other mechanics could comment on this.

[jarhead99]

Originally Posted by 97Concours1

Did you buy the car? I don't think head gaskets take time to seal. I think they either seal or leak right from the beginning. From all I've heard, adding sealant doesn't work. If you have to add sealant, I'd be very concerned and would probably not buy the car.

Maybe some other mechanics could comment on this.

Is it possible that the hydrocarbons in the overflow could have been left over from the original leak before the HG repair? (this was also suggested) The mechanic said there was a very small amount. Perhaps I should pass on this vehicle. There seems to be too many angles and no real way to confirm. I would hate to get stuck with an expensive vehicle that is in need of repairs.

[97Concours1]

Originally Posted by jarhead99

Is it possible that the hydrocarbons in the overflow could have been left over from the original leak before the HG repair? (this was also suggested) The mechanic said there was a very small amount. Perhaps I should pass on this vehicle. There seems to be too many angles and no real way to confirm. I would hate to get stuck with an expensive vehicle that is in need of repairs.

Leftover hydrocarbons are possible I suppose. I've never done this test, I've just read that it is the best way to determine if a head gasket is leaking. I don't want to scare you away from buying this vehicle. It might be a great car. It's just a gamble with these Northstars either way. If the head gaskets haven't been repaired, you take the chance that the head gaskets will eventually go. If they have been repaired, you wonder if it was done right.

Maybe you could try posting a question down on the main Northstar section and see if some mechanics would respond.

[AJxtcman]

Please look at this. You need a login to see the pictures.
I may repost over here

Root cause failure