Great compression and oil on the plugs

I pulled the spark plugs to regap them on my newly mobile Jeep and a few had darker brown plugs with pretty wet oil on the threads. The motor is a 258 in a 75 cj5. I dont know the history aside from speculating it had been rebuilt at some point due to the solid 75lbs of oil pressure when cold.

I decided to run a compression test and about fell over-all were 140-160. I guess it makes sense because it idles smooth like butter most of the time.

So I am thinking that a possibility is a few of the valve seals/guides dried out from sitting and is leaking a bit. It does smoke when firing it up cold and puffs a little blue smole when quick revving it. Any other thoughts?

 

sounds like leaking valve seals to me.
My '74 258 does the same thing.
Runs great, good compression, and even passes emissions.

 

Yup, sounds like valve stem seals. Has all the symptoms. Might try running a slightly hotter plug if you can to help keep them from oil fouling.

 

Awesome, thanks guys. Thats what I was thinking.

@ Patrick-I did a few months ago pull the pvc and it rattled around fine. They are cheap though so maybe Ill replace it anyway.

 

Patrick, I think you may be right. I pulled the carb to rebuild it today and found a bunch of oil in the intake. I always thought when the pvc stopped working it would clog and not allow anything through. Does this sound like a symptom of a bad pvc valve?

 

oil in the intake....hmm pcv

 

Yup, that did it! Thanks guys, the easiest repair ever at $1.99 and a minute of labor and no more smoke. Only problem now (well, not the ONLY one) is I think she sat to long and the rear main seal dried out. :evil: Its not bad but I took her out on the highway for about 20 miles today, came home and had a nice little puddle under her after about 10 minutes.

 

just markin its turf...

 

Haha, I can dig it in parking lots, but I hate oil on the garage floor. Anyway, replaced the main seal and oil pan gasket tonight instead of studying for my midterm tomorrow. Priorities, ya know. The previous owner had gouged it pretty good putting it in. Anyway, trial by fire in the morning cause Im driving it to class. Letting the

On a different note, anyone used a felpro one piece oil pan gasket for that lately? Those are really trick. Never seen one like that before. With the ribs and rings inserted for the bolt holes.