Blown headgasket??
Melting Slicks
Joined: Nov 2010
Posts: 2,216
Likes: 113
From: Michigan
More pressure is not always good, it can mean a restriction. For example a clogged filter and that's why some have a bypass and GM puts a bypass in sbc oil filter adapters(I'm not sure if corvette is different). People have blown off oil filters.
Thread Starter
Instructor
Joined: May 2013
Posts: 177
Likes: 0
From: Fairland Oklahoma
Oil filter is new so it shouldn't be clogged. I'll check my pcv system just to be sure I don't blow another gasket.
And yup it's an l98. And yeah I didn't think about the confusion from my username lol that's actually the year I was born.
And yup it's an l98. And yeah I didn't think about the confusion from my username lol that's actually the year I was born.
Le Mans Master
Joined: Dec 2006
Posts: 5,139
Likes: 482
From: H-Town Texas
And '95, holy cow, I've got boxer shorts older than you.
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
There should not be oil in that hose if the PCV system is working correctly.
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Thread Starter
Instructor
Joined: May 2013
Posts: 177
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From: Fairland Oklahoma
Depending on the year, some L98 throttle bodies have a vacuum hose on the passenger side that goes to the vapor canister under the driver's side headlight. There is also a vacuum hose on the bottom of the throttle body that goes to the EGR solenoid.
That is the air supply for the PCV system. It takes filtered air from the throttle body and feeds it into the crankcase through the passenger side valve cover. On the driver's side, the PCV valve gets vacuum from the intake manifold to suck the oil vapors out of the crankcase. I recently found this little diagram (which is not for a Corvette, but the general idea is the same -- the PCV valve is connected to the lower intake, not the plenum):
There should not be oil in that hose if the PCV system is working correctly.
That is the air supply for the PCV system. It takes filtered air from the throttle body and feeds it into the crankcase through the passenger side valve cover. On the driver's side, the PCV valve gets vacuum from the intake manifold to suck the oil vapors out of the crankcase. I recently found this little diagram (which is not for a Corvette, but the general idea is the same -- the PCV valve is connected to the lower intake, not the plenum):
There should not be oil in that hose if the PCV system is working correctly.
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
At high RPMs the hot oil gases may be forced out through the breather tube and into the throttle body. I noticed on mine it makes a lot of smoke from the breather filter that I converted to at high RPMs.
Melting Slicks
Joined: Jun 2013
Posts: 3,065
Likes: 39
Thread Starter
Instructor
Joined: May 2013
Posts: 177
Likes: 0
From: Fairland Oklahoma
Would there be any change in idle if either side of the pcv hoses were unplugged? I unplugged them and nothing changed about the idle. Also there's nothing happening on the passenger side from the throttle body. No suction or air passing through at all
Race Director
Joined: Apr 2002
Posts: 10,036
Likes: 346
From: Anaheim CA
If you have oil in the passenger side tubing it usually means the PCV system is not working. Basically the only way to get oil in there is if the blowby is overwhelming the PCV system. That usually only happens in full race engines operated at WOT and high RPM (low vacuum at WOT) for sustained periods of time. That said, worn piston rings can cause this, but that is not at all common on these engines.