Restrictive Push Rods.....Still Too Much Oil !!!!!
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From: SoCal
Restrictive Push Rods.....Still Too Much Oil !!!!!
Well I was getting too much oil flow up in the valve cover leading to oil being pushed out the valve cover vent tube thus into the intake. I catch most of this with a catch can setup.
Smith Brother restricted push rods were supposed to cure this. Well I got them and it made absolutely no difference. I fill up the Elite can with oil after a 30 minute track session !!!!!!!!!!
DH
Smith Brother restricted push rods were supposed to cure this. Well I got them and it made absolutely no difference. I fill up the Elite can with oil after a 30 minute track session !!!!!!!!!!
DH
Thread Starter
Team Owner
Joined: May 2004
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From: SoCal
I wonder if the coalescing filter is too restrictive in the PCV line causing the oil to flow easier up top.
Or maybe this engine too has blowby pressure.
Or maybe a check valve is necessary in the valve cover vent line.
Or what else ....... ?????????
DH
Or maybe this engine too has blowby pressure.
Or maybe a check valve is necessary in the valve cover vent line.
Or what else ....... ?????????
DH
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Joined: Dec 2000
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From: San Diego CA
Your coalescing filter is downstream of your AMW can - correct? If the filter were too restrictive, you'd have less oil in the AMW, not more. GM is offering more restrictive orifice fittings to replace PCV valves in some vehicles. This means (to me) that some restriction is not bad. Still, I doubt the filter is clogged unless your oil is unfiltered or you don't change your oil enough - both highly unlikely in your case!
Thread Starter
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Joined: May 2004
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From: SoCal
Your coalescing filter is downstream of your AMW can - correct? If the filter were too restrictive, you'd have less oil in the AMW, not more. GM is offering more restrictive orifice fittings to replace PCV valves in some vehicles. This means (to me) that some restriction is not bad. Still, I doubt the filter is clogged unless your oil is unfiltered or you don't change your oil enough - both highly unlikely in your case!
My coalescing is down stream of the AMW in the PCV line. It is not collecting unusual amounts during track sessions. It is the Elite can in the valve cover fresh air line that is completely full of fresh oil after thirty minutes. This line has that coarse white stone filter (flows much more), not a coalecsing down stream of the Elite.
DH
Le Mans Master
Joined: Aug 2001
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From: Bradenton FLORIDA
With the engine running at idle, take off your oul fill cap and feel if there is pressure pushing out. If so it sounds like blow-by....possibly the ringland broke on #7 (just a guess since it is the one that almost always breaks). Let us know.
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From: PNW
http://forums.corvetteforum.com/show....php?t=1884012
I think the only real fix for guys who spend a lot of time at WOT is to have a well baffled breather on the valve cover and block off the fresh air tube on the throttle body.
Le Mans Master
Joined: Mar 2002
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From: PNW
Your coalescing filter is downstream of your AMW can - correct? If the filter were too restrictive, you'd have less oil in the AMW, not more. GM is offering more restrictive orifice fittings to replace PCV valves in some vehicles. This means (to me) that some restriction is not bad. Still, I doubt the filter is clogged unless your oil is unfiltered or you don't change your oil enough - both highly unlikely in your case!
So DH ... have you tried the fixed 2.5 mm orifice PCV "valve"?
The key to making the PCV system suck vapors out of the crankcase and make up the evacuation with fresh air is to make crankcase vapors flow from the valley cover (on LS6) to the intake manifold and not backwards through the fresh air make-up path.
To do this with the current design, the path from the valley cover must have less resistance than the path from the valve cover to the throttle body when under WOT conditions.
Le Mans Master
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From: PNW
I've heard of engines with massive ring blow by will actually blow the dipstick up out of the tube during WOT use, as the crankcase pressure is so high that it has to go somewhere, and the PCV system can't handle the flow so it blows the dipstick out of its tube.
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I wouldn't say a fixed 2.5 mm orifice is more restrictive than the original PCV valve. Remember that at idle, the PCV valve is almost closed, and the flow rate is small. At WOT the PCV valve opens up some under it's internal spring pressure based on manifold vacuum level. Hard to say how the flow rates would compare, but a 2.5 mm seems like a decent sized orifice in this application.
So DH ... have you tried the fixed 2.5 mm orifice PCV "valve"?
The key to making the PCV system suck vapors out of the crankcase and make up the evacuation with fresh air is to make crankcase vapors flow from the valley cover (on LS6) to the intake manifold and not backwards through the fresh air make-up path.
To do this with the current design, the path from the valley cover must have less resistance than the path from the valve cover to the throttle body when under WOT conditions.
So DH ... have you tried the fixed 2.5 mm orifice PCV "valve"?
The key to making the PCV system suck vapors out of the crankcase and make up the evacuation with fresh air is to make crankcase vapors flow from the valley cover (on LS6) to the intake manifold and not backwards through the fresh air make-up path.
To do this with the current design, the path from the valley cover must have less resistance than the path from the valve cover to the throttle body when under WOT conditions.
Thread Starter
Team Owner
Joined: May 2004
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From: SoCal
Thread Starter
Team Owner
Joined: May 2004
Posts: 26,345
Likes: 232
From: SoCal
My last motor did the exact same thing. So on this new engine (has 4500 miles) I was hoping this would not be an issue with the Smith Brother push rods
So I kinda doubt its anything broken. But how would you know??
I did do a very long and hard canyon run without any appreciable oil collected. So some of it may be from the high speed lateral forces on the track.
DH
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Team Owner
Joined: May 2004
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From: SoCal
I've mentioned this many times ... that the crankcase gasses will take the path of least resistance. If the flow path from the crankcase to the intake manifold is more restrictive than the path from the valve cover to the throttle body then you will get flow backwards down the fresh airline. Even if both paths were about the same resistance, you may still get flow backwards down the fresh airline at WOT, high crankcase case production conditions because both the intake manifold and throttle body are at about the same vacuum level at WOT. In other words, at WOT the system acts like it has two parallel paths to the intake system and crankcase gasses could flow down both paths.
http://forums.corvetteforum.com/show....php?t=1884012
I think the only real fix for guys who spend a lot of time at WOT is to have a well baffled breather on the valve cover and block off the fresh air tube on the throttle body.
http://forums.corvetteforum.com/show....php?t=1884012
I think the only real fix for guys who spend a lot of time at WOT is to have a well baffled breather on the valve cover and block off the fresh air tube on the throttle body.
DH
Thread Starter
Team Owner
Joined: May 2004
Posts: 26,345
Likes: 232
From: SoCal
I wouldn't say a fixed 2.5 mm orifice is more restrictive than the original PCV valve. Remember that at idle, the PCV valve is almost closed, and the flow rate is small. At WOT the PCV valve opens up some under it's internal spring pressure based on manifold vacuum level. Hard to say how the flow rates would compare, but a 2.5 mm seems like a decent sized orifice in this application.
So DH ... have you tried the fixed 2.5 mm orifice PCV "valve"?
The key to making the PCV system suck vapors out of the crankcase and make up the evacuation with fresh air is to make crankcase vapors flow from the valley cover (on LS6) to the intake manifold and not backwards through the fresh air make-up path.
To do this with the current design, the path from the valley cover must have less resistance than the path from the valve cover to the throttle body when under WOT conditions.
So DH ... have you tried the fixed 2.5 mm orifice PCV "valve"?
The key to making the PCV system suck vapors out of the crankcase and make up the evacuation with fresh air is to make crankcase vapors flow from the valley cover (on LS6) to the intake manifold and not backwards through the fresh air make-up path.
To do this with the current design, the path from the valley cover must have less resistance than the path from the valve cover to the throttle body when under WOT conditions.
DH
Thread Starter
Team Owner
Joined: May 2004
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From: SoCal
DH
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