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Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
I dont know what this means. The motor is new crate with vortec heads. No water-oil mixing in the crankcase. Is it a bad filter? The pics are what I found when I popped the hood....
is it just pressure from 3500 - 4200rpm and over 40psi oil pressure or do I have a problem????
I dont see any other leaks and yes I have been keeping tabs.
86-90s 350vortec 274cam 850rpm idle, 0 other leaks about 300 miles total on motor
Last edited by budget builder; Oct 31, 2019 at 09:55 PM.
If its a fresh engine, perhaps the rings have not seated. Have you done the heavy throttle accelerations needed to build the cylinder pressure to help seat the rings. Also those breather filters always seem to leave an oily film on the valve cover even on a healthy engine. At WOT the baffles in the valve cover will always allow some oily vapors to escape as the PCV valve ceases to function in the absence of manifold vacuum.
Do you have baffles in those valve covers? Sometimes they are missing. PVC system only works under vacuum, once vacuum is gone crankcase pressure will push out of breather. You might want to consider a catch can if your going to run an open system.
Last edited by 3.4 grape; Nov 1, 2019 at 06:40 AM.
Go hammer on it to seat the rings. Driving lazy is terrible fornew motors. Then check for oil leaks. Alot of oil could be thrown up to the top end making its way out the breather hole. Esp with rpm, or combined with blowby from fresh motor
Go hammer on it. Now your speaking my language.... oh yeah
A catch can is plumbed to the valve cover and traps the blowby oil vapors by condensing them in the can.
My break-ins are always foot to the floor. With a flat tappet cam I break in the cam. Check for leaks. Then take it out and seat the rings. I try not to take them over 5K until it is broken in. Just don't sustain high rpm or high speed for the first 500 miles.
Do you have baffles in those valve covers? Sometimes they are missing. PVC system only works under vacuum, once vacuum is gone crankcase pressure will push out of breather. You might want to consider a catch can if your going to run an open system.
Not totally accurate. The PCV valve is more of a one way valve as opposed to a vacuum actuated on/off switch. Here is a picture of a PCV valve that I cut open
The spring keeps the plunger from making a seal against one side. Flow can enter opening A and exit opening B but if flow tries to go from B to A the valve closes because the plunger is pulled toward it's seat. Flow can go from A to B whether it vacuum pulling from side B or compression(blow by) going from side A to B. The flow is going the same direction it's just one method is pushing it and the other method is puling it.
I read that if the engine happened to backfire, that plunger would snap shut, to prevent the chances of a flame from going straight into the crankcase.
I read that if the engine happened to backfire, that plunger would snap shut, to prevent the chances of a flame from going straight into the crankcase.
It will snap shut. The valve will be pushed against it's seat because the backfire would come up through the intake and then toward the PCV valve which only allows air to move toward the intake.
What you are seeing has NOTHING WHATSOEVER to do with oil pressure.
The REAL cause is, those … [insert words describing manufacturer's impaired brain function here] "breathers", coupled with KROME valve covers that most likely don't even HAVE baffles.
Put some STOCK valve covers on it, and a properly configured PCV system. Problem solved.
Whatever that crap is you posted about PCV valves, is PURE UNVARNISHED UNADULTERATED BOGOSITY. There have been … what … A BILLION cars or so, made with them? How many cars have you seen sitting by the side of the road because of … whatever you asked about? So how "bad" of an idea are they, on account of ... that?? Right.
