Opinions needed - build up under valve cover. 97 Explorer yard engine.

[todd.gorman]

Gents,

Finally got my hands on a 97 5.0 Explorer engine from a yard and started to tear into it a bit to see what I got. First there seemed to be a pretty good build up of oil in the plenum just after the throttle body. I assumed this was somewhat normal since the EGR and valve cover vents just in to there. But then I pulled off the valve covers. On the RHS there is a crusty build up on the rear side (opposite to filler/vent). On the LHS there is the build up the entire length. Is this normal for a 'closed' system on the EFI engines or do I have some valve seat/seal problems? I pulled all the plugs and they looked quite good.

 

[73azbronco]

That looks fine to me (well, maybe someone missed an oil change or two but still OK) , you might consider using synthetic as that would clean that area up over a period of time.

 

[chadomatic]

It looks fine to me. I would run an oil flush when you get it running. I recommend BG 109. works great and will clean out everything.