1997 STS head gasket replacement next week

[KHE]

If i were to split the case, is it a prety straight forward task? Unbolt, clean and reseal?

Also, being the block is aluninum, if i do split the case is there any chance that the lower case treads will back out with the case bolts? I noticed this with the head bolts. Several head bolts that i removed had the blocks treads stuck in them. Obviously thats the reason for doing this project. However i don't want to have to repair the case 1/2 treads. The lower block is so covered with oil, i really can't even tell where it was leaking from but i figured this was the option to reseal the case.

If i do reseal it, can i use Loctite 5910 which is what i use on all my snowmobile and bike cases, or should i go with the GM sealant?

I didn't see this post earlier - it doesn't matter now since the engine is back in the car. Use only the GM sealant to seal the crankcase halves and oil manifold plate. There is NO aftermarket product that will work. The instructions in the bulletin need to be followed explicitly. Have all the parts and tools ready as the engine needs to be torqued within 30 minutes of sealant application.

The engines I've repaired smoked at startup - mostly from the cutting/drilling oil that runs down the block sides during the Timesert process. It will become less and less over a day or so.

[mudweiser]

If i were to split the case, is it a prety straight forward task? Unbolt, clean and reseal?

Also, being the block is aluninum, if i do split the case is there any chance that the lower case treads will back out with the case bolts? I noticed this with the head bolts. Several head bolts that i removed had the blocks treads stuck in them. Obviously thats the reason for doing this project. However i don't want to have to repair the case 1/2 treads. The lower block is so covered with oil, i really can't even tell where it was leaking from but i figured this was the option to reseal the case.

If i do reseal it, can i use Loctite 5910 which is what i use on all my snowmobile and bike cases, or should i go with the GM sealant?

I didn't see this post earlier - it doesn't matter now since the engine is back in the car. Use only the GM sealant to seal the crankcase halves and oil manifold plate. There is NO aftermarket product that will work. The instructions in the bulletin need to be followed explicitly. Have all the parts and tools ready as the engine needs to be torqued within 30 minutes of sealant application.

The engines I've repaired smoked at startup - mostly from the cutting/drilling oil that runs down the block sides during the Timesert process. It will become less and less over a day or so.

I didn't do the case. Once the motor was on the stand it looked like all the leaking near the front timing cover seal and the oil filter lines. I replaced the o-rings, front seal and oil pan gasket. It solved the problem. The car would drip just sitting there, and it's fine now.

The car still smokes out the exhaust now. However it's about like any car would smoke during a cold start up. I have only had it running for a few 10 minute warm up sessions. It seems to be less smoke each time. When the head gasket went, you cuoldn't even see the cars behind you from the stop lights. Thats something i'll never forget, funny but embarrasing.

[BodybyFisher]

Once you have stabilized everything a few WOTs might reseat the rings and stop that smoke you are seeing.

You could also be burning off junk from the head gasket problem and job

[mudweiser]

Took the Caddy for a spin today, about 10 miles. I need to replace the coolant fill cap, it allows the overflow hose to drip but the motor is not hot. I need a few cans of R-134A to rid of the A/C warning and repalce the battery. The motor seems to crank slow and a load test shows it as marginal. The motor had good power, smoking seems to be less and less with time.

Darn ABS and traction lights are on. I'm planning to wait until i get a battery and some more run time on it before i pull codes. It's pretty dissapointing having a 300HP motor taking off in second gear though. The thing is just a kitten at idle, but as soon as you load that motor with WOT you can hear that deep growl. If this car does get sold, there will be another Caddy to replace it. I just have to find a decent year STS w/o the N* issues. I have to say, i didn't mind spending the cash on 91 octane. It was a good feeling to gas it up once again.

[BodybyFisher]

I am glad its running better and better

When you straighten out the battery, run the codes and see what comes up for the ABS

[KHE]

Took the Caddy for a spin today, about 10 miles. I need to replace the coolant fill cap, it allows the overflow hose to drip but the motor is not hot. I need a few cans of R-134A to rid of the A/C warning and repalce the battery. The motor seems to crank slow and a load test shows it as marginal. The motor had good power, smoking seems to be less and less with time.

Darn ABS and traction lights are on. I'm planning to wait until i get a battery and some more run time on it before i pull codes. It's pretty dissapointing having a 300HP motor taking off in second gear though. The thing is just a kitten at idle, but as soon as you load that motor with WOT you can hear that deep growl. If this car does get sold, there will be another Caddy to replace it. I just have to find a decent year STS w/o the N* issues. I have to say, i didn't mind spending the cash on 91 octane. It was a good feeling to gas it up once again.

Did you plug in the ECTBM module on the driver's front side of the engine bay down low? That could be the problem. As far as looking for a Cadillac without Northstar issues, you now own one! After repairing the engine it will last for many years - it is stronger than when it was new.

[toddthor65]

I have a 97 seville and all of this summer to replace the head gaskets. You had mentioned earlier that you you would try and lift the body over the engine. How did you get this done? Did you use an engine hoist? I really don't want to pull the motor out the top because I know it will be a pain to line up the tranny again.

[mudweiser]

I used an engine hoist, bought some 2500 # chain and some hooks from Northern tool. The hooks were good for like 1,800 lbs each. We used 4 hooks. 2 on each side. There is spots on the frame rail right where the front nbumper slides. We put the hooks in there and lifted the car. It really went pretty easy. I can't post pics on here, but if you get me an e-mail i can send you some pics of the process.