ok this is probably one of those "newbie" posts that is gonna come back to haunt me but I fugred what the hell

98 TJ with 38K ... I was going through oil at about 2 QT's per tank, I did a compression test.... 170 @ all 6 cylenders (thats good I think) so then my logic was valve seals... 2 weeks ago I replaced all the valve seals and gave it a good healthy dose of seafoam everything seemed fine

Today I noticed it was shootin out black stuff out the tailpipe AGAIN!! When I gave it gas and watched.. I could have sworn I saw bluish smoke and black stuff shoot out afterwards which would tell me the oil is burning but cant figure it out in my head how its getting in there to be burnt (maybe I need engine 101... I looked at howstuffworks.com if that helps :flipoff2: )

so now I'm lost...
piston rings?
pistons?
cylender Head?

I dont dabble much into motors hence I'm new to this portion Can someone be kind enough to give some suggestions...

I really dont feel like takin apart this motor... what a bitch

Is it possible / plausible that the catalytic converter or muffler is all filled with crap by now from the amount of oil you were burning before? It would suck to tear apart the engine, re-ring it and everything and find out that it was the cat or muffler all along. Both of those get for sure hot enough to burn the oil, producing the blue smoke and soot and miscellaneous crap you're getting. Having a non-catalyst vehicle i'm not really sure about how plausible this is -- only that its quite possible. Anybody got any other ideas like that? Not that a rebuild is that hard but its a pain to do right and most certainly not on the cheap side :shaking:

hey strangers,

Yeh what 78J said. Is it using oil? I thought the seals took care of that and the roughness issues.

i'll be back on campus later next week for a few days if you need a hand with it (hopefully you get it sorted out before then).


you're right, this should be in the newbie section.

ok this is probably one of those "newbie" posts that is gonna come back to haunt me

Yup, newbie it is.

Try doing a leak down test and see what you get.