illbeatdanielhuls

I have a 90 gt...and since its been supercharged it stared having an oil leak. I finally realized its the pcp (i think thats what its called) valve so i replaced it and it come undone a few hours later. My mechanic told me that its probably because the a ring is shot...so i was wondering if i could replace a ring myself.. and what work had to be done to do that.??? Thanks

FoxGT

You will have to push the pistons up a little out of the block to see. It could be done with the engine still in the car, but it won't be easy.

roundman

if the pistons rings are that bad, then you need to pull the engine and get it rebuilt by a professional shop.

90GTRagtop

Actually it's a PCV (Positive Crankcase Ventilation) valve, and if the rings are that bad, roundman is right, complete rebuild time. However, you should be able to determine that with a compression test. Also, the PCV normally works by using intake manifold vacuum to pull the fumes from from the crankcase into the intake and then burn them through the motor. I have never had the pleasure to play with a supercharger, but maybe one day. However, I know the principle (using power from the crankshaft to improve airflow by means of a blower pressurizing the intake). I'm not sure how a PCV would work in that circumstance, but I'm pretty sure it would have to be connected to the intake side of the blower. If it's on the pressure side, it will not work right. Even though the PCV is a check valve (one way flow) it could leak by. Even if it doesn't leak by, if it's pressurized and the crankcase fumes cannot pass through, they will pressurize the other side and blow the PCV out (only pushing through a rubber grommet hold it in). Older engines vented to atmosphere before the advent of basic pollution control laws. Since you said it happened after the supercharger, the first thing I would check is the proper connection of the PCV hose piping.

vfast

it's not the rings..your engine is building up pressure....I had this problem as wel...what psi are you running?..I don't use a pcv valve or the hose from the valve cover to the T/B ..no leaks..also pull the screen out of the pvc hole on the block

msbarr884

It seems that I have the same issue. I am running a 302 bored 0.030 over with a procharger supercharger. I have 14# running on it and the bastard at high RPMs wants to spit oil out the dipstick tube. This tells me the crankcase is pressurized preventing my rings from sealing, and robbing power. When under boost, how do i vent the crankcase?

stanglx2002

why dont you put a breather on the oil fill tube to let some of the pressure out

Quik

alot of lightnings and cobras put an oil catcher in line with there one hose to catch the oil. look into one of thosee. i guess this is normal for boosted applications

90GTRagtop

Uuummmmm......... Let's see. We're talking about a pressurized mixture of fuel and air venting through the bottom end of the motor out into the engine compartment while picking up a mist of oil. To me, that doesn't sound like a good thing. I wouldn't want it venting into the bottom end for starters, much less to vent out where the mixture can find neat things like hot headers or a spark from a wire that breaks down after exposure to gas & oil. Along with loosing a small amount of boost, the potential fire hazard would be a concern. I'd seal off the PCV from downstream of the blower, and if I wanted it to go into the engine, I'd make sure it was on the intake side of the blower.

Tims 88GT

stanglx is right you need a breather to let your pressure out, that is the best way, yes they make a little mess but it is cheep and easy.