Stock 440-6 barrel restoration engine, the PCV Valve is pulling in oil after rebuild wetting inside intake and fouling plugs. Engine holding 18 steady vacuum and I have done a compression check and find all cylinders at 165 psi. There is stock valve covers on the engine with baffle so there is no direct oil being splashed on the valve. I'm at a loss any ideas ?
Engine ran on dyno with no pcv and of course ran awesome, rings sealed right up and made 410hp 470 torque.
Thanks MLR426
Are you sure that the oil is coming into the motor from the PCV or is it possible that the oil is sucking into the intake from the lifter valley pan? I've seen a lot of rebuilt motors, especially cast iron six pak motors, suck oil into the motor from the lifter valleys from a bad seal on the intake valley pans
To test this remove the PCV from the valve cover and remove the hose from the intake or carb, you could leave the PCV sit outside the valve cover with a rag wrap around the bottom of the PCV to keep debris and dirt from sucing into the motor also and leave it hook up to keep the vacume the same
I have taped a rag over the PCV hole in the rocker arm cover to see if crankcase pressure is blowing oil out of the valve covers to test issues like this also
Lots of gremlins in these motors, dang it
If you try this test drive the car long enough to suck all the oil out of the intake, if it doesn't dry up in 100 miles of street driving the valley pan may be your problem
I now set the intake manifolds on the motors without the valley pans and use a feeler gauge to check the manifold to head fitment on all four corners at the top and bottom of each corner, I write it down on the intake corners for future reference
I've seen some that have .015 on the bottom of one corner and have .007 at the top of that corner, I've also seen .000 on one corner with .025 on the bottom on the same corner
I shoot for having the manifold cut to fit the motors with .002 max at the bottom and no more than .005 on the top so the valley pans will be pinched in tight at the bottom
I also will use the thin intake gaskets to help seal up the intake from sucking oil into the motor
IHTHs
Let us know what you do and find