The 460 in my 76 F350 camper special with 70K miles is blowing (slinging?) oil out the dipstick tube, and through the crankcase breather into the air cleaner housing. I've checked the PCV valve and lines and everything seems to be in order--valve is new. Any ideas on why pressure in the crankcase is so high? Power is excellent; I've had the valve covers off and the rockers/top of heads, etc. are clean, with no deposits. Engine doesn't smoke, but I usually have to add a quart of oil after 1500 highway miles--most of which is to replace the leakage from dipstick and crankcase breather. I'm the original owner of the vehicle, and it has been "babeyed" since "birth". Cylinder pressures are within Ford's specs. I've recently noticed that the oil pressure guage reads almost at the "H" on the factory guage when at highway speeds. I haven't had a chance to hook-up a mechanical guage to verify pressure, but could high oil pressure be causing this? All suggestions/comments appreciated.

Thanks

 

High oil pressure shouldnt cause this. One idea is that maybe your PCV and breather are on the wrong connections. One sucks, one blows, to put it mildly. If they are both blowing, or if neither is sucking back into the intake, then you will end up with excessively high crankcase pressures.

Best of luck to ya..Ill post again If I think of anything else.

J/.c

1965 Ford Galaxie 500 (okay, so not quite a truck)
460/C6 transplant @ 389hp/491 lb.ft.
14.29@103.8, 13-14 mpg heheheheheh

 

Now that I think about it, High Oil pressure may have something to do with it. If too much oil is flowing to the valve cover area, and your valve covers are unbaffled, then you may be spitting extra oil off your rockers into the breather hose..which would explain the oil in that area..
The Dipstick still has me baffled, though. Ill keep thinking.

J/.c

1965 Ford Galaxie 500 (okay, so not quite a truck)
460/C6 transplant @ 389hp/491 lb.ft.
14.29@103.8, 13-14 mpg heheheheheh

 

Thanks for responding; yes the crankcase vent and PCV are connected correctly. PCV to the appropriate port on the carb, and the crankcase vent hose is connected to it's spot on the air filter housing. I rechecked the PCV "plumbing" this morning and idled the truck with the PCV valve removed. Oil was gurgling almost to the top of the valve cover opening, and was spattering out the opening. I'm pretty sure none of the oil drain down passages are plugged because the engine is too clean. As I said in my original message, although it's a 76, the truck only has 70K miles--that's less than 3K per year. I change the oil and filter every 4 months, regardless of miles. I should have the mechanical oil pressure guage connected tomorrow, and will verify the pressure.

I'm kind of stumped with oil coming out the dip stick opening, too. I believe the tube in which the dip stick is guided to the oil pan terminates in the pan, for oil to come out the dip stick opening, the pan must have some pressure build-up. Let me know if you have anymore ideas.

 

Unless they changed the 460 from earlier years, the drainback holes from the rocker area are big. One at the back of each head, behind rockers for cylinders 4 and 8. If on a steep downslope where oil wouldn't get to the back holes, oil would exit to the valley area via the pushrod holes up by cylinders 1 and 5. Are you seeing oil foaming up, or literally solid oil level up at the filler or PCV? If your dipstick is up front through the timing cover, the dipstick tube itself is very short, just enough through the timing cover to get the stick angled right to make it down to the front edge of the pan. Passes by the cam and crank gears and timing chain. The opening between the front of the block and the inside surface of the timing cover is about 2 inches front to back down at the pan. Can't believe that the whole timing case is filled solid with oil, don't think there's enough oil to do all that and still have some in the sump for the oil pickup. Do you have a blowby problem? Is there a lot of airflow (blowby)out the filler and PCV when you have them off?