Crank Case Pressure Problems?
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Crank Case Pressure Problems? A friend of mine with a 95 LT1 car has problems with oil being blown out of his breathers on his valve covers at WOT, throws oil on the headers and smokes really bad, not really seeing any performance problems since his hot cam car put down i think 347RWHP which is dam good (6 speed car). We got rid of the breather and replaced it with the stock PCV hose from the throttle body to the valve cover but it still has this problem. Any suggestions?
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From: Ringoes/Flemington, New Jersey
Originally Posted by SRZ
Put your hand over the hole and if you feel air coming out it's the rings.
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I appreciate the compliments guys, its been a long work in progress and i still have ideas to help accent a bit more. Thanks Guys
He had 2 breathers, one on each valve cover and still has the problem. Now what you guys are saying is that i should pull the breather off and if i feel air pushing my hand away then his piston rings are bad or what? He said he thinks he sees blue smoke behind him when he gets on it, but hopefully its not the rings.
He had 2 breathers, one on each valve cover and still has the problem. Now what you guys are saying is that i should pull the breather off and if i feel air pushing my hand away then his piston rings are bad or what? He said he thinks he sees blue smoke behind him when he gets on it, but hopefully its not the rings.
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We both have mellings high performance oil pumps, i love my oil pressure stays between 40 and the 3rd notch depending on rpms with no problems, im assuming his acts the same way, 3 other guys with LT1's with us have the same oil pump so that shouldnt be it, an oil pump should be able to do that anyways
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From: Ringoes/Flemington, New Jersey
you should read up on what those breathers do.
its for the PCV system (Positive Crankcase Ventilation)
Its obvious that your combustion chamber cant be sealed 100%, so there is "blowby" gases past the piston rings. this is what puts vapors into your crankcase. The objective of the PCV system is to take those vapors, and cycle it back into the intake system. thats why you see hoses running back into the intake manifold, or air cleaner (carbourated systems).
But, the PCV system can get overwhelmed, and this is mainly caused by excessive blowby from the pistons (shot rings). My oldsmobile toronado failed emissions because of this. Cylinder 3 was dead, the PSI reading was about 40psi. the plug was fouled. There was so much blowby in the PCV system, that it was making the car so damn rich at idle.
You have to take the breather off and feel/look for excessive blowby
its for the PCV system (Positive Crankcase Ventilation)
Its obvious that your combustion chamber cant be sealed 100%, so there is "blowby" gases past the piston rings. this is what puts vapors into your crankcase. The objective of the PCV system is to take those vapors, and cycle it back into the intake system. thats why you see hoses running back into the intake manifold, or air cleaner (carbourated systems).
But, the PCV system can get overwhelmed, and this is mainly caused by excessive blowby from the pistons (shot rings). My oldsmobile toronado failed emissions because of this. Cylinder 3 was dead, the PSI reading was about 40psi. the plug was fouled. There was so much blowby in the PCV system, that it was making the car so damn rich at idle.
You have to take the breather off and feel/look for excessive blowby
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Yea, i knew the blue smoke was oil burning. But i will admit, i am pretty ignorant on the functions of the PCV system, so essentially the rings are not sealing the combustion chamber effectively allowing much of the gases to "blow by" and this is evident by the inability of the PCV system to handle this and oil blowing through. What kind of problems does this entail, the car has been running very strong, every time we race its dead even and i have a bigger cam (still no dyno tune though which he has) so his car is running great other than spitting oil out, will it eventually deteriorate over time and him loose compression completely in one or more cylinders?
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From: Ringoes/Flemington, New Jersey
check the spark plugs if u can. see if they have any oil on em or not. but if you have lots of blowby comin out of the PCV, then you've got ring issues. how does the car run at idle and under heavy load? (not WOT)
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We just did a plug change recently, i didnt notice any oil but ill ask him since he took the majority of them out. It runs like a champ, i mean it put down 347RWHP at wot with this problem, at idle its fine and under normal driving conditions you really dont notice anything, the only problems are the oil blowing out of the valve covers and the burning oil (blue smoke). We noticed a lot of his vacuum lines for the PCV set up weren't correct so we're going to mess with it some to see if it helps but with the filters it blows out pretty bad
no good haha 
God. Yeah, ok, fix what's wrong first. Modern emissions computer engines will not run right with 'old school' breathers. Fix the pcv system.
Check also that the oil is not leaking out the rear of the valve cover, tighten cover bolts a bit if loose. Mine dripped oul on headers, all it was was the valve cover needed a bit more tight.
And for what could happen, oil on headers = car burns to ground...
Check also that the oil is not leaking out the rear of the valve cover, tighten cover bolts a bit if loose. Mine dripped oul on headers, all it was was the valve cover needed a bit more tight.
And for what could happen, oil on headers = car burns to ground...
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From: Ringoes/Flemington, New Jersey
Originally Posted by Boodyrider
God. Yeah, ok, fix what's wrong first. Modern emissions computer engines will not run right with 'old school' breathers. Fix the pcv system.
PCV uses vaccum to remove gases from the crankcase. in order to create a vaccum, you need to add air, and remove it. so it takes outside air, then uses manifold vaccum to suck it back into the intake so it can burn the gas.
