blow by?


New Member
Oct 14, 2003
400 miles on the build ,i have 120lb cyl pressure on all but one cyl,it has 80.Im assuming i have a ring seating issue.Also have a fuel smell with a little smoke coming out of vc vents at idle but when i get in on it, it smokes a good bit.Is it time to pull the motor down and put a better ring in?

didnt realize they were chromeoly
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ok, wet compression test compared to dry does help. and your results do suggest a ring problem. that works.
Like hissin said, do a leakdown test. 10% or less is good, 5% is great. Anything higher suggests you have major ring issues. Make sure you read up on the procedure as there are a lot of things/guidlines that you go by to tell what signs mean what *rings, valves, seating, ect.).

It does however seem like, no offense, cheap piston rings - either that or poor install that lead to damage upon installation.
i believe they are cheap rings,i didnt do anything different than the last few times i installed rings,i guess ill see if the leakdown test fails.i have a funny feeling it will end up in a tear down

another test i ran is i took the rocker arms off on that low cyl and put about 100lb of air in the cyl and felt a good amount of air coming from the oil drain holes in the head,seemed alot less air came from the other cyl