fan belt

[tcninc]

every time we race our 914 74...in an autoX the fan belt comes off (high reves). Normal daily driving no problems. Any one out there give me some ideas..

[Joe Browne]

Check your pully alignment. If thats not the prob you might have to get new pulleys made that are deep groved. I had that problem with my drag car.

[JP Noonan]

When you check the alignment, take the fan off and look for either a 1/8" spacer between it and the crank or a pulley for the air conditioner. If there was A/C on the car that was taken off, the PO might have taken the pulley too and not replaced it with a spacer.

[Dave at Pelican Parts]

My car used to do this as well. At first it happened any time I got up to (about) the redline. Then it only happened when I hit the rev-limiter. Eventually it stopped.

It seemed to stop around the time that I R&Rd the alternator, but I'm not sure that was a factor. You might try loosening up the bolts that hold the alternator bracket onto the fan shroud. That *may* allow enough movement of the alternator (and thus the plane the pulley rotates in) to line it up with the fan pulley. Not sure how you'd measure this precisely without fabbing up a bunch of custom brackets, though....

This doesn't sound like much help now that I've read it through. Sorry bout that.

--DD

[doug minar]

This happened three times during a time trial.The alt. bracket is cheesy and the tighter I got the belt the more the bracket would bend. I straightened it with a pry bar and was carefull when I tightened it again.
I asked other 914 guys and the same thing had happened to them and it was also an alignment problem.My belt is still on after about 6 events
Doug