i have a 97 expedition with a 4.6 and i have a e oil
leak leakin onto my catalstic converter and smoking changed the rear main seal (when we got it apart found it wasnt rear main it was dry ) valve covers arent leaking so im thinking maybe intake leak ? anyone else had this problem open to ideas thanks

 

I doubt it would be the intake since I do not think oil travels through it. Headgasket would be the other place you could develop an oil leak.

 

there is no oil at all that travels under intake i thought there was a plastic shield under upper intake?

 

Is it the passenger side cat that's smoking?
If so, you've got a head gasket leaking on the rearmost edge of the head when the oil feed passage feeding the camshaft/valvetrain is located.
JL

 

ya thats what i feared most thats what we figure at first but had alot of PROFESSIONALS say they highly doubted it would be a head gasket but looks like im not gettin off cheap on this one. now do you think its required to get heads and deck done when changing gaskets ? or if we straight edge the heads and they look good we just do gaskets?

 

DO NOT let just any shop resurface those heads. There is a very specific finish Ra that MUST be on the heads for the gaskets to seal properly. I've never seen one of the iron blocks that needed any surfacing or deck work, and very few heads, it's mostly just the gasket, and the design of the head that puts that oil passage at the rearmost edge of the head in a location that has the potential for leaks or seepage if the gasket is not absolutely perfect. The other head does it, but that oil passage is behind the timing cover, so you just don't see it there, and it doesn't hurt anything.
JL

 

is it goona be safe for the engine to drive the suv for a couple of months as long as i keep an eye on the oil?

 

Depends on how much oil is leaking. if it's enough to catch fire on the converters, then I wouldn't, or would be VERY careful if I did drive it. If it's like my work truck, and is just a bit of light smoke/smell-just drive it 'til you can get it fixed. That '01 F150 has 255K miles on it now, and the passenger side head has been weeping a bit of oil since approx 70K miles.
JL

 

ok thanks jl

 

i have the same problem on my 97 4.6. i have recently had the heads removed and valves done and the deck milled and then reinstalled. i still have the oil leak and smoke from the exhaust burnign the oil. are there any other possible places that may cause the leak? i found one post that said something about an oil plug on the back of the head that may be leaking but i cannot find any such thing.