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Discussion Starter · #1 ·
well my quistion is i did a compresion check on one of my motors every cylinder was 119 except # 1 ,it was 90 to me thats not exceptable,what might i be looking at,new motor 496 blown intercooled let me no
 

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Compression not relative. Too many variables. Valve lash,gauges, etc.
Leak it down if you want to know about cylinder sealing.

Then check the valve lash.
 

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why did you do a compression test it the first place? was it running bad or something? misfire? noises? the reasoning behind the compression test might be helpful if you are looking for a problem with the engine.

AP
 

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Discussion Starter · #5 ·
it was blowing steam out the puck tank breather witch is not a bad thing ,it just never did it before so i was concerned,lost a little power so motor guy said check compresion ,then a leak down,well found out that its coming up to the valve covers,there for rings,was hoping a valve not seating but not the case
 

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I was alway taught that if the air comes out the dipstick, then its the rings. If it comes out the carb or exhaust then its valves.

Did you get anything at the dipstick? What was the leakdown % ?
 

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Compression not relative. Too many variables. Valve lash,gauges, etc.
Leak it down if you want to know about cylinder sealing.

Then check the valve lash.
x2 on this.

also on a blown app as this it's going to have some decent ring gap and piston to wall clearance to boot as it should. maybe a warm engine would give better results to your leakdown.

i thought in your other post this is a new engine? how much time is on it?

dont give up were just getting are tools out. :D
 

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it was blowing steam out the puck tank breather witch is not a bad thing ,it just never did it before so i was concerned,lost a little power so motor guy said check compresion ,then a leak down,well found out that its coming up to the valve covers,there for rings,was hoping a valve not seating but not the case

Check for a blown head gasket. It shouldn't be blowing steam out of the puke tank.
 
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