low compression

[scheffler]

OK so my compression is 125 123 127 125. So it is even but it is low. So who knows why? The car runs like *** but it idols fine. I have no oil in coolant or the coolant in oil. I had a some oil on plug 1 but that seemed to be a one time thing there isn't any oil on it after i put it back in and drove around my block. I really don't know what would cause my compression to be so low and even on all cylinders. I put a cap of oil into cylinder 2 to see if the compression went up and to see if the rings are bad. It didn't change anything it went up like maybe 5psi. I have 8.5 compression pistions

So what do you guys think that it is.

[480sx]

Check your comp with a different compression tester. Time wears on those things.

IIRC 8.5's should be in the neighborhood of 150 psi.

[troll's 240sx]

you know what i have 8.5 compression arias pistons and my compression registers at 130 psi on all four also. I got about 3500 miles on it right now, but when I first checked it at 1000, they were at 170. I really dont know if this is right also.

[ghx407]

I've had 8.8 Arias pistons for about a year now. I've checked the compression on several occasions during the past 12 months and have always gotten ~155 psi accross the board...

Someone correct me if I'm wrong, but yor compression results don't sound too bad for 8.5 pistons...
Modified by ghx407 at 5:25 PM 5/13/2008

[scheffler]

well I just know that when I checked them last they were 150psi across. And know it is 120psi .

I guess they are fine from what you guys are telling me?

[ghx407]

I'm not saying it's perfectly fine, because IMO 8.5 pistons should give you at least ~135psi compression... But your numbers don't seem too off from that, I guess.

[480sx]

How did you break the motor in?

[scheffler]

well i bought the motor with 1000 miles on it. I also ran it for about another 500 with out a turbo. It has about 5000 miles on it now.

I dont think I have a problem any more I think that i was just being paranoid. Cause of oil on lpug one.

So the oil on plug one? bad valve seal?

[480sx]

Sounds like thats most likely the culprit. Its def not coming from your crank case.