Paul902

I'm half way through changing my belts and found my old alternator belt is the 757 mm version, but the new one is the 760 mm version. Can I use it or should I get the 757 mm version?

Steve Weiner-Rennsport Systems

The 760mm one is for the Twin-Turbo. Use the 757mm one on the N/A cars.

Paul902

Thanks, Steve.

Garth S

Hey Paul,
Two wraps of duct tape around the pulley should take up that 3mm of slack - good to go

IXLR8

Paul,

My 993 owner's manual calls for a 9.5 x 760 La.

But what was installed on my 993 before the belt failed last year was a 9.5 x 757 LA, part number: 999 192 372 50.

It was replaced with a 9.5 x 760 LA, part number: 999 192 343 50.

Paul902

I'm fresh out of German duct tape though.

Paul902

Thanks for the call! Mine is an M64-23, a diy I have printed out calls for the 760 mm for this variant, too. Maybe I should try it, although the dealer put a 757 mm on 9 years ago and it has worked fine. I have two shims in there I could remove if need be...

911PERVY

PET shows a 776 for the n/a and a 760 for the turbo...........is PET wrong?

AOW162435

I thought the updated pulley called for a different belt?


Andreas

IXLR8

Recent PET (see post #5 above) shows a 760.

A 757 came previously installed with 2 x 0.7 mm shims. The listed 760 that I installed was far too tight with those same shims that I installed a third 0.7 mm shim.

geolab

?????

911PERVY

OK, thats a fan belt, the OP was about an alternator belt...........

IXLR8

I'd expect a new belt to be tight, but here was one longer than the replacement and it needed a third shim...go figure. But it is tensioned correctly now.

cmat

Here's the service bulletin that gives the alternator belt used with the revised pulley:
757mm for Turbo and 760mm for Carrera

Paul902

Thanks, Chuck. I do not have the updated pulley, so it looks conclusive that the 760 mm belt should be correct. As stated, I previously had a 757 mm on there and it worked fine for years, but the 760 mm should be the correct belt for me. I installed it on the weekend, but haven't turned over the engine yet since my engine carrier is currently in the trunk of my A3!