Mechanics

REBUILT ENGINE LEAKING OIL

Ford Mustang

Recently rebuilt engine in a 2000 Ford Mustang with 3.8 V-6. The engine was machined and reassembled with new pistons, rings, ect. #3 cylinder si leaking oil so bad as to foul the plug where it will not fire. #6 plug is dirty on inspection, but is still firing. Is it possible that I have a bad valve seal even though they were all replaced, or maybe the rings did not seat on those two cylinders? It puts out a little blue smoke and also has a strong oil smell when it is first started. Thanks for any advice you can give.
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Tj53
June 14, 2007.



Question did you rebuild the motor, a local shop rebuild it or was it pulled and taken to a machine shop and they rebuilt it? We will go fom there. Note why was it rebuilt as the motor is a beast!

Tiny
Fordmadza
Jun 19, 2007.
The engine was rebuilt because it was doing the same thing. Burning oil and fouling the plug to the point of misfiring. I pulled the engine and and took it to a machine shop. They did all the machine work and put new pistons on the rods. I took all the parts back home and assembled it myself and re-installed it.

Tiny
Tj53
Jun 19, 2007.
The blue smoke and smell sounds like the valve guides are severely worn. New valve guide seals won't do the trick, even if they are the positive contact type. If umbrella type seals were installed, then you could have oil leaking down into the intake runners.

Generally rings that haven't seated won't cause blue smoke at startup. But during hard acceleration!

Tiny
Indyuke
Jun 22, 2007.