D.I.Y. 993/964 single belt conversion

Frank 993 · 06-19-2009, 04:27 PM

Hi everybody,

After 2 months of blissful motoring in my 1995 963 cab. my first problem:

The alternator quit working.

No big deal as I have a very good rebuilding shop nearby but the strange 2 speed fan bearing was not making the right noise ie none so I went to my bearing store only to be told sorry OEM only

I called Porsche in Montreal and got a price of $240

for the whole hub with bearing.

I looked at the board and sure enough there was a solution : the rs style hub with a single pulley but dealer never heard of such a thing and even with part no. can't find anything.

So... I had a machinist do me one it is surprisingly easy, you do not need the whole thing just a spacer of same dimension as the bearing and another one to replace the outer pulley once tightened it spins as a single unit just like the rs hub.

Pictures will follow shortly.

HiWind · HiWind's Garage

sadly they didnt

billjam · billjam's Garage

Yes, this is quite a simple mod. There are two ways to go about it.
One is as Frank described ... by replacing the bearing and outer pulley with separate spacers so that the hub is sandwiched between them.
The other way is to use one spacer to replace the bearing and the pulley. Disadvantage of this method is that the spacer needs to be fixed to the inside of the pulley hub (tack weld or grub screw).