Hello,
I have a type III engine on a sandrail, recently rebuilt. The type III is the engine with the fan mounted to the crank (as opposed to the type I, which has the fan attached to the alternator/generator).
The engine ran fine for two weekends after the rebuild, but has recently developed a serious oil leak.
I'm getting oil leakage into the fan housing, which is blowing oil out all over the engine, dripping out the bottom of the fan housing, etc. I'd say it's going through something like 1/2qt per hour. This is with the engine initially filled to 2.5qts. Oil pressure is approx 25psi at idle, 50psi at 2500+ rpms.
Can someone explain to me what is supposed to seal the rear (pulley-end) of the VW engine? Looking at the back of the engine, there is the oil slinger (inside the case, of course), and then the fan, and then the pulley. Are the spiral threads on the fan responsible for keeping the oil from getting out?
My VW book (keeping your VW alive) says the threads "must be clean, or they will throw oil". Can anyone explain to me how these threads work? Is the leakage at all sensitive to the amount of torque that the pulley nut is torqued?
I'm not sure how the oil is leaking into the housing. If I take the fan off and run the engine (for a very short while), then of course oil slops out at a pretty good rate (I'm assuming that is normal with the fan/pulley removed), but if I put the fan in, I can't see where the oil is coming from.
Thanks, Scott (owner of the sandrail from hell)