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boost leak ?

4doorboost

Well-known member
Joined
Aug 19, 2008
Messages
208
Location
Westlake Village, Cali
im about two hours north i actually went to sdsu so that drive is nothing, i have 9.1 compression pistons so im thinkin it should be a little higher, and my rings are def leaking a little bit. but im gunna do the test later witht the throttle open and see what happens. are you talking about a boost leak test cause i leakdown test is different. if you tdc one cylinder that means the valves on another cylinder would be open, but my problem is pressure getting into the oil i can hear it
 

4doorboost

Well-known member
Joined
Aug 19, 2008
Messages
208
Location
Westlake Village, Cali
so i think im gunna do a test at the throttle body to elimate the turbo just to make sure its not the turbo seals, if it still bubbles after that i think its gotta be my rings, i cant think of anything else that would be causing this
 

AnotherNewb

Well-known member
Joined
Apr 25, 2010
Messages
1,472
Location
Orlando, FL
Are you sure its bubbling in your oil? To me I would think coolant would be more likely. Like a leaking head gasket. Rings wouldn't sound like bubbles since they are not submerged in oil.
 

SouthCaliVR4

Well-known member
Joined
Jul 31, 2010
Messages
984
Location
North county San Diego
well, your certainly welcome to bring it down where my toys are & we can get it checked out. hows it running?
 

mikus

Well-known member
Joined
Jan 11, 2007
Messages
2,763
Location
Aurora IL
Slow down guys - you're trying to find itty bitty leaks, and a few days later you think your rings are shot?

First- even at 10psi any significant air leaks should be whistling. Boost leak test - find them - fix them. Done.

Next- if it'll help you sleep, do the compression/leakdown test. Do not correlate rings with boost leak test.

As for why oil is bubbling? Here's a possibility. Turbo seals are somewhat reliant on oil pressure pushing 'out'. With no oil pressure, and you pushing 'in' with all that air, some air can slip by, go down the return, and bubble up your oil (where else is low enough in the pan to cause the oil to bubble?) Not a huge deal. I'm not saying this is what's happening, but it's likely enough that you shouldn't freak out without other symptoms.
 

4doorboost

Well-known member
Joined
Aug 19, 2008
Messages
208
Location
Westlake Village, Cali
its not coolant i have no coolant issues and the car runs super cold plus i never lose any coolant. i can def hear the oil bubbling when i do a boost leak test through the oil cap, and the only way to get this would be if the air going into the cylinder is getting past the rings and therefore pressurising the crankcase, also known as blow by. i know its not the turbo seals because when the turbo seals go bad the motors tend to smoke badly. i have 9to1 compression pistons so i feel like my compression in the cylinders should be more than 160 across. its seems to me like the rings didnt seat properly during break in or they were improperly installed. my car runs fine, idles good, the only thing is on idle i get low vaccum around 12-13 but i do have cams. i would come down to sd man but i dont know what the point would be, i think im gunna pull my motor and have RRE put new rings on her, its not even that expensive, just a PITA
 

BPU925

Well-known member
Joined
Jul 3, 2010
Messages
124
Location
katy, tx
you could have a bad PCV valve if you have it hooked up....thats the only way i could see air getting into your valve cover?....thats if your rings and seals are good which by your numbers you posted i would say are ok
 

4doorboost

Well-known member
Joined
Aug 19, 2008
Messages
208
Location
Westlake Village, Cali
i just bought a brand new mitsu valve a week ago, plus if that was the case then the air would be coming out of the valve cover but the oil would not be bubbling, the air is def getting into the crankcase, my compression #'s arnt bad and my motor runs good but it does eat a little oil about a half quart or so every 3000. i think my rings just didnt seat or maybe were installed wrong but they are good enough. its just when boost is applied i think it squeezes past the rings...
 
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