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1.8 compression results help

Old 06-20-2016, 07:15 PM
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Default 1.8 compression results help

So i did a dry test on a supercharged motor, the spark plugs were pretty drenched with oil and the results came out

-170
-150
-165
-160

valve cover seems to be leaking. Since its a car im interested in buying, i dont have a compressor to do a leak down test and didnt think to do a wet test while i was at it. But considering the variation with cylinder 2, is this a NO GO?
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Old 06-20-2016, 07:16 PM
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not no go, but definitely not healthy
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Old 06-20-2016, 07:19 PM
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What are your plans with the car? Are you going to build on top of what the previous owner has done or are you prepared to have a motor waiting for you when this one goes?

12.5% difference; I'd like to see under 10, but it could be super worse. #2 is a bit dodgy, might be able to just break it down and hone/re-ring the cylinders and be fine
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Old 06-20-2016, 07:21 PM
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rule #1: no BP get's re-built with stock rods and re-used rings
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Old 06-20-2016, 08:10 PM
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Originally Posted by psyber_0ptix View Post
What are your plans with the car? Are you going to build on top of what the previous owner has done or are you prepared to have a motor waiting for you when this one goes?

12.5% difference; I'd like to see under 10, but it could be super worse. #2 is a bit dodgy, might be able to just break it down and hone/re-ring the cylinders and be fine
id like to keep it as is and have some fun with it for a bit but if the motor dies i wouldn't mind paying to have it rebuilt with better internals. Just don't wanna drive it home then run into issues very soon.
That oil on the spark plugs could easily be the valve cover gasket right? Not sure if that compression result is very bad or not

Last edited by markooo89; 06-21-2016 at 01:37 AM.
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Old 06-20-2016, 10:36 PM
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Originally Posted by markooo89 View Post
id like to keep it as is and have some fun with it for a bit but if the motor blowd i wouldnt mind paying to have it rebuilt with better internals. Just dont wanna drive it home then blow it 2 hours later loll
that oil on the spark plugs could easily be the valve cover gasket right?
hard to rebuild with a rod sticking out the side, something to think about.
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Old 06-21-2016, 09:56 AM
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Oil on the spark plugs could very easily be a VC gasket. I have seen that many times before. Compression numbers a a bit wide spread then I would like to see, but I have seen far worse on running cars.
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