Rings bad??

RachGST · 07-03-2008, 06:18 PM

Ok, so I tried to search for this answer to a question I had. I took off my oil pan to replace the gasket and also at the same time I was adjusting my timing. When I rotated the crank by hand, I could hear the compression in the cylinders coming out from underneath where I was at. I wanted to know if that is normal or if I have bad rings? The car doesn't smoke or anything, but I have been having trouble with it not running right in my other posts. Thanks guys.

Jeff99GS · 07-03-2008, 06:44 PM

Its perfectly normal to have some blow by...do a compression check when you get the oil pan back on if you want to know the condition of the piston rings.

1996dsm · 07-03-2008, 08:30 PM

what are decent compression check #'s?

talon187 · 07-03-2008, 08:45 PM

im not sure with the nt cars but on a turbo 1g its 150 is pretty much perfect 2g turbos have high compression pistions

Jeff99GS · 07-04-2008, 02:02 AM

Normal compression is usually around 170 for a 2g....but the service limit is around 110-120 for the 4g63t

the 420a im not sure on but I think Normal is around 190-210....and the service limit is like 110-120

If your Compression is LOW, then add a cap full of oil to the cylinder you're testing through the spark plug hole.
Now Re-test your compression adding oil to each cylider as you go...If the compression went up cause of the oil you added then your rings are worn.

If the compression does NOT go up cause of the oil, then its leaking somewhere else. Like the Headgasket or the Valves.

1996dsm · 07-04-2008, 04:18 AM

thanx

pj91gsx · 07-04-2008, 01:33 PM

Quote:

Originally Posted by Jeff99GS

Normal compression is usually around 170 for a 2g....

My friend's 2g GST had 180 for all the cylinders in a car with 107k miles on it.

RachGST · 07-04-2008, 01:59 PM

thanks for the replies guys.