[Pontiacman]

Started the 250 OHC 4-bbl, last night I got oil coming out the oil filler tube,.Did a compression test 135 lbs all 6cylinders, no oil on plugs. but if you rev-engine and hold at 2000rpm, oil massively comes up oil tube.oil pressure is where book says it should be.don't have pcv in place yet,Hope I don't have to take apart,motor sounds to good ,how long for rings to seat?gutted a plug and put air to each cylinder,comes out behind carb.not down in crankcase.Is there a baffle at bottom of filler tube?Didn't have factory air cleaner assy this motor.this is about my 10th motor I've rebuilt myself, not much info this motor, fairly rare.I have 69 manual everything it corresponding to book stats,comp. press., oil press.why is oil coming out filler tube?All the
pictures of this motor I have show exhaust side
of motor.seems like there should be a baffle to
stop oil from flinging, like crank scraper

[ April 13, 2002: Message edited by: Pontiacman ]</p>

[F-1Rodder]

I would say that the oil filler tube must be the only pressure vent and that the bottom of the oil filler is in the oil bath therefore the only way the engine can vent the bypass pressure is out the filler tube. That motor must have been vented some other way and you now have it plugged with a different manifold, valve cover or whatever that is nolonger vented. As you know, bypass pressure is normal, it needs to go somewhere, but not through the oil bath first.

[Tom]

install the PCV it will relieve some crankcase pressure or install an evacuator system.In an inline engine there is no large areas except for the crankcase so most of the pressure is located there(in a V engine there is room in the lifter valley to take up some of the pressure)so the dipstick tube becomes the vent