Hi,
My 13B with a T04B turbo is starting to smoke at idle and it really
has me worried. The engine is in my autocross car which has approx.
6 events on it since it had a complete engine and turbo rebuild.
The car is not street legal so I probably have less than 2-3 hours
on the motor. The problem stated to develop last weekend and is
really no better this weekend.

The car starts instantly. Does not smoke until it comes up to
temperature. It will smoke as I idle through the pits, smokes
heavily as I leave the line, then appears to be clear during the run.

At this point I don't know how to differentiate from the problem
being turbo seals, internal to the motor, or even a problem with the
turbo oil drain line (drains into the front cover).

I would really appreciate any experience or diagnosis that anyone
has that will help me troubleshoot this without pulling everything
and having it all rebuilt again.

This was not a problem when everything first went into the car, and
the power continues to be great.

Thanks in advance for your expertise.

 

what kind of smoke. black or blue. and take of your intercooler pipe to see is large amount oil inside. if so most likely your turbo is going bad

 

Well the vent line was the problem. I vented the oil fill tube to atmosphere and the smoke stopped. I emptied the catch tank, shortened the vent tube so that it does not go very deep into the catch tank, raqn the motor for 15 minutes and the problem appears to be solved.

Apparently the crank case (I know this is the wrong tem for a rotary) builds up pressure and if it can not vent, it creates a small amount of back pressure in the turbo oil drain line. The back pressure is high enough that it forces oil through the turbo seals rather than letting it all drain back into the engine.