89 supra turbo last cylinder filled with oil??
 

i have a 89 turbo supra 7mgte, its not running right now so i was changing plugs, first off cylinder 3 plug was clean and wet with gas so im amusing the wire or that side of the coil is dead, but when i got to the back cylinder i took the plug out and it was completely coated in oil like i just dipped it strait into a bucket of it...what could that all be about?? any help would be appreciated, Thanks.

Leaking valve cover gaskets are the most common culprit... I'm assuming oil was on the top and on the threads?

yeah all the way down on the threads, and looking into the cylinder it was all on top of the piston. but thinking about it now it probably just ran into the open plug whole then i took it out and ended up on the piston that way.
so your thinking just a bad cam cover gasket??

If oil is on the threads it wasn't in the cylinder to begin with... thus, yes, it came from outside the cylinder. As I said, the cam cover gaskets are a VERY common leak point. Age and over tightening by previous owners causing shrinkage and compression as well as the screws backing out over time are the most common sources of the problem... sometimes you'll find one where the cover is warped or even cracked due to someone getting a bit too overzealous while tightening them down. The torque spec is 22 INCH pounds, That's just a good, firm HAND TIGHT with a phillips screwdriver (make sure you use one the right size for proper transfer of power... a #3 IIRC). Some people recomment swapping to bolts as the only way to go... they're NO better at all.... just easier to get a solid grip on, but they're also easier to overtighten, especially to the point of causing damage.

Whatever fastener you use put on new grommets and if you like, some blue loc-tite and tighten to spec... no more.


EDIT: Oh, and other causes include a crack in the head or a leak at one of the three bug hex plugs in the center or a crack in the PCV plumbing.

alright, thanks for the info man, il check it out tomorrow