nastee383

Oil to be sucked into the combustion chamber through the intake ports. I have a PCV and a breather, valve covers are baffled, valve guides are good and I have teflon PC valve seals. Intake valves are caked with oil on top and there is an oily film in the ports of the intake.

MotorHead

My L48 was going thru alot of oil and I did not know why. When I did the engine swap I took the intake off and found that all my intake valves had oil caked on top.

I found where the oil was going and just assumed it was going down the guides from either bad seals or guides or both.

TLChydraulics

I don't know if a gasser would be as bad as my deisel, but when my deisel's air filter starts to get a little dirty it starts sucking air from the crank case and of course starts to use a good amount of oil. Alternatively if your motor has a lot of blow-by, it can cause oil usage as you describe also.

I'll cross my fingers for you that you have a dirty air filter.



Good luck,

Loren

OkeeGuy

this happened to me once on a motor we built...
we bought the heads used and come to find out, they had been shaved too much, changing the way the intake mated up to the block...
when looking closely at the front of the engine, we could see that the mating of the intake and heads was not parellel (sp)...they had a slight gap towards the bottom, causing oil to flow into the intake runners...
took us a while to figure that one out!
it was so bad that oil was running out of the tailpipes!
i abruptly returned the heads and bought some new World Product sportsman heads end of problem...

pik

Sounds like a problem with the intake gasket not sealing correctly.

Tiredol74

Hard to tell w/o more info . Has this happened suddenly or been jus worsening over time? I see you run for ET. Some high performance street/race engines with high pressure/volume oil pumps require crankcase evac systems. One I heard of with similar problems was said by builder to have porous casting on the intake? However, knowing the manufacturer it's hard to believe. If PCV valve ok, breather n filter clean could try addn'l baffled PCV grommet. Aside from those already mentioned here rings are a possibility.

thebruce

I posted pics of the same problem not too long ago. I have Trick Flow heads, and the tech folks there asked what I had used to seal the rocker arm studs. My response was "....uhhhhh..." Turns out I had forgotten to seal them. I have pulled and sealed them now, but I haven't put new plugs in to see if my oil burning is over. The explanation made sense, though, and there was definitely oil on the threads of all the intake studs.

Good luck!

nastee383

The car doesn't smoke visibly. When I had the heads done a couple of years ago there was the same problem. The machinist told me at the time the guides were good but I had teflon PC seals installed. Since I took the motor out anyway this time to change the cam I decided to get some more headwork done and there was the same problem. The machinist again said my valve guides were good. I think the problem may be with the intake. I had my intake Jet Hot coated a few years ago and upon closer examination it looks like the sealing surface has some irregularities because of the coating finish. I'm gonna have it smoothed out to get a good, flat sealing surface. I'll also have the machinist seal up the rocker studs when he puts them back together as another poster suggests.

MotorHead

What heads do you have ?

GrandSportC3

I had the same problem with my engine... I was burning lots of oil because there wasn't enough evacuation and the pressure just built up. The oil got past the rings, intake gasket and would also be sucked into the engine through the PCV system... High performance engines just build up a lot of pressure.. I installed a crankcase evacuation system that fixed the problem... However - the system that I've installed in my vehicle only works on cars without mufflers.. I'm running open sidepipes... The only systems that I could think of that would get enough evacuation on a car with mufflers would be a zero pressure system (running hoses from the breathers to a overflow canister) or a vacuum pump...


[Modified by GrandSportC3, 10:14 PM 7/1/2004]