intermittent smoke help??

[Hick]

My 87 MJ 2.5 4spd 2wd will run fine when i start it cold, i can drive it all day with no problems. I shut it off for about a minute and crank it over and it smokes like seafoam and runs like crap. just smells like exhaust, not coolant or oil. Its not eating coolant or oil either. If i drive it about 200 ft it stops and won't smoke again until i kill it and crank it again. WTF is going on in my 2.5??????

 

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[Pete M]

holy crap! that's a new one by me. :(

[jimoshel]

I had a bad valve stem seal do that. Would only do it when shut down for a couple minutes, then started again. Start it and as soon as the smoke starts diminishing shut it off. Then pull the plugs. The leaking one will be oily, sooty. Actually shut it off while it's still smoking good, before the soot burns off. On the one I had didn't have to pull the plugs. Upon removing the valve cover the mutilated seal could be seen at the bottom of the valve stem.