Just finished compression test

[talonDSMerr]

From cylinder 1-4: 150, 150, 120, 80.
The car still runs and drives fine, but loses power after 4000rpm. Can worn rings cause compression to drop so much? There are no coolant or oil leaks, but I think the head gasket is blown between cylinders 3 and 4. What other causes could there be? How might I go about fixing? I am kind of torn between buying a longblock and trying to rebuild it myself. In the end, won't they both end up costing about the same amount? Thanks for any input.

 

[talonDSMerr]

Not a good idea dude...dont ruin a good six-bolt....just break down and pull the head. It will take a weekend and guaranteed you would find the problem...that or get a REAL leakdown tester and do it right. Such a bad conclusion to come to.

I didn't say I was going to ruin it. A "real" leak down tester will only tell me what % is leaking. I need to know where it's leaking and I couldn't hear anything after pressurizing it to 95psi. It's not like it's running horribly, it's just not 100%.

 

[axloverstreet]

from left to right 1-112 2-130 3-130 4-55!!!!! WTF

i think i need rings or somthing in that nature


what do you guys think?

 

[TFFC]

If it has white smoke, that means it burning coolant, Have you had to fill up your coolant overflow alot? How many miles on the engine? You need to do a leakdown test to confirm what the problem is, my guess is a head gasket. Your not to far from me, let me know what you come up with

 

[MichaelSuch]

Has your car ever overheated? If it hasn't then I doubt the rings are shot... You got the headgasket and studs already, so just pull your head, take it to your local automotive machine shop and have them check it out (basically a valve job, check the valves for any bends or kinks, check the valve guides, have new valve seals put in and then have them pressure test it too of course and make sure that the head hasn't been warped).

 

[Defiant]

from left to right 1-112 2-130 3-130 4-55!!!!! WTF

i think i need rings or somthing in that nature

Yes, those will be part of your new engine. Take better care of the next one. This one has a melted piston, or possibly a valve. No need for any further testing: it has to come apart.