Not Running Well After Overheating and Replacing the Head Gasket

[ffearless]

After replacing the head gasket, I have 130, 130, 115 compression. But the car doesn't want to idle, is low on power and revs up slowly. Any suggestions?
It was running great before overheating. 2004 mt with 181,000 miles. The grid charger has the battery at about 179v. I cleared the codes and no new ones are set.

[retepsnikrep]

Where was the gasket leaking could you tell?

Was it the cylinder with the lower compression?

Double check everything went back together correctly and check tappets.

Did you keep the timing chain on the sprocket in same place or might it have moved a fraction?

Fuel pressure OK?

[ffearless]

It leaked in 2 & 3. 3 has the low compression. I will check valve clearance. I thought I kept the the sprocket in the same place, just to check, what does TDC cam timing look look like? The fuel pressure looks good. The spark plugs look darker than normal.

Originally Posted by retepsnikrep

Where was the gasket leaking could you tell?

Was it the cylinder with the lower compression?

Double check everything went back together correctly and check tappets.

Did you keep the timing chain on the sprocket in same place or might it have moved a fraction?

Fuel pressure OK?

[Eli]

Unfortunately those are very low compression numbers, near the lower service limit. They should be 180-200PSI with a healthy engine.

Burned valves? Did you have the head checked for warpage and reworked if necessary?

[ffearless]

Originally Posted by retepsnikrep

Where was the gasket leaking could you tell?

Was it the cylinder with the lower compression?

Double check everything went back together correctly and check tappets.

Did you keep the timing chain on the sprocket in same place or might it have moved a fraction?

Fuel pressure OK?

Originally Posted by Eli

Unfortunately those are very low compression numbers, near the lower service limit. They should be 180-200PSI with a healthy engine.

Burned valves? Did you have the head checked for warpage and reworked?

The shop surfaced the head .006" and found no leaks or cracks. The valves were all good. I had no idea these cars should have that kind of compression. There was no measurable ridge at the top of the cylinder. Could the rings have worn that much? If it is that bad, maybe I should buy a lower mileage motor to drop in it. My lifetime average is 62, but I had to drive carefully and keep speeds in the mid 50s to do it. It should be a lot easier with a nice tight motor.

[Eli]

It seems unlikely that the rings are worn if it ran well before the overheat. I dunno, hard to say.

I've been meaning to get a compression test in on the 448k mile car, it would be interesting. But yes, people typically see 180-230+PSI, even on high mileage engines. Maximum variation at any PSI is 28PSI, and Minimum compression is specced at 128PSI in the service manual.

Your LMPG and speeds seem reasonable, depending on your local terrain and conditions.

[Willie Williford]

Check the shop manual Eli, you may be off a little...........Wait I'll go outside in the workshop and get my manual...."Back".....See page 2-2....STANDARDS and SERVICE LIMITS...Under Engine Assembly.
HTH
Willie
I was shocked to when I replaced my leaking head gasket, after doing a compression check.

[ffearless]

I have never seen compression that high. It would be interesting to see what it is in my K1300s at 13:1. My best motors back in the day ran like 175 psi.

[retepsnikrep]

Don't forget the compression test is supposed to be performed with the 12v starter not the IMA ASFAIK

[Eli]

That's true and that has probably confounded things.

My information came from this thread:

Engine Compression Testing