mysterious oil loss

[93rangemaster]

I'm not sure how or where it is going.... but it is going...
I bought the truck, ended up having to replace both heads with fairly freshly rebuilt ones, replaced all intake manifold gaskets and head gaskets, all felpro. I'm getting roughly 160-170psi on all cylinders, I have yet to find any oil drips under my truck. I'm somehow losing a quart every 2 weeks tho... any guesses? the valve stem seals seemed pretty minty

 

[john93rangerstx]

if ur not leaking it u are useing it

 

[RonD]

Yes, there are only 3 ways for oil to get out of an engine:
1. drain plug when you are changing oil
2. exhaust system when you are burning oil
3. gasket leak when you are dripping oil

Half a quart a week should show under the vehicle, I use a piece of card board under an engine, move it around each day if its a smaller piece.
A rear intake leak could travel down the bell housing and appear as if the trans was leaking.
Cam or Crank seal leak would be right at the front of the engine.
If it is an upper engine leak the hot exhaust manifold/pipes can burn/evaporate most of it but you should smell that or at least see the residue on the exhaust system, stain.
Lower side of each valve cover gasket has oil sitting on it, so is the most common place for a leak, but usually the easiest to see and fix, look at the exhaust manifolds for stains, oily residue.

If you are burning it you will see the tell tale blue smoke at startup, and when shifting gears on a manual trans., warm engine starts are the best time to watch for that.

 

[93rangemaster]

thanks for the replies. It's weird, there is zero blue smoke ever, so I'll have to check more thoughly for leaks

 

[jaydees]

Did you ever figure out where your oil was going? I ask because I'm in a simialar situation. I also replaced the heads, gaskets, etc. The truck runs strong with good compression. The bottom side of the engine is completely dry, with no leaks. I have checked the PCV system and actually ran it without as a check. I've also replaced the lower intake gasket again using the OEM Ford gasket (in case it was sucking in air in the lifter galley).

My only two thoughts are 1. A defect in the reman heads, like a valve guide or seal bad. 2. Oil rings on piston(s) stuck and not wiping the cylinder properly.

One would think that I would be leaving a smoke screen going down the road, but that is not the case.

I am actually pulling the heads now and just stopped for the evening. I just pulled the lower intake and it looks good. However, there is oil in the horizontal portion of the intake port of the head. If you wipe your finger across the surface it is definetly oil. So oil is entering the combustion chamber, it is just a matter of figuring out where.