My freind has a 98 24 valve. It starts easy ,no miss sounds good but theres too much presure in the crank case. There is a steady blow out of the oil fill cap when its off . Ive read in here trying to figure this out. I have a hard time believing its something broke inside because it sounds good. Is it the turbo ? Any suggestions on what to check ? When we took the cowl off the turbo we could see pieces of some kind of material in the space around the front of the turbo . is there any way the turbo could blow into the case? Any help would be appreiciated.
Wesley

 

Block off the vacuum pump inlet and see if it still blows. The way the vacuum pump works (it dumps the evacuated air into the case) if there is a leak it will be pressurizing the case. Normally the vacuum is used to run the HVAC controls, cruise control, 4X4 CAD, and on older models the brake booster. If the blowing goes away after you block off the pump inlet you know you have a leak somewhere else in the vacuum plumbing. Good luck and I hope this fixes the problem; if not things can get more serious. As for the turbo, the only way imaginable for it to pressurize the case would be through it's drain tubing but I have no idea how the mechanics of that kind of mess would work.

 

Right on the vacuum pump not being able to hold a vac in the HVAC and front axle interlock (if equip) vacuum circuit.

 

I will drive down there later tonight to check the pump
Thanks

 

Easier way that I check for vacuum leaks:
Run the engine for a few minutes, shut it down and wait a few, disconnect any vacuum line, you should hear a hiss. If not you have a leak. Even a small leak will drain the vacuum rapidly. On the other hand a system with no leaks will hold vacuum for days if not weeks without the engine running.

 

I don't know if the 24v is the same as a 12v, but if the motor is being pressurize wouldn't it the crank case breather tube that's plugged.

 

Sometimes it's more pressure than the breather can handle. The restriction of the breather is a part you can't see easily, the screen over it inside the motor.This screen can become clogged if a person runs gasser motor oil. Diesel motor oil is designed to keep soot in suspension, gasser oil isn't and will leave sludge deposits throughout the engine clogging the breather screen.