Dudley

Does anyone have a copy of the Porsche TSB for the pully update.?
Is there a pdf version lying around?
Are both upper pulleys changed out or just the alternator pulley?

Thanks

Mike J

Here is the text, sorry for the poor formatting, I have to get to work!

Cheers,

Mike

PS: PM me if you want the TSB

---------------------------------------------

Vehicle Type: 911 Carrera as of M.Y. 1995 and 911 Turbo as of M.Y. 1996
Model Year: As of 1995 (S)

Concern: In case of alternator belt failure or belt noises in conjunction with pulley,
part number, 993 106 268 00 (s/s to 993 106 268 01), the alternator belt
and pulley must be replaced.

Information: 911 Turbo:
When repairs are necessary, install only the new version belt and pulley halves.

Description Part Number
New belt (1 ea.) 999 192 372 50 (757 mm long)
Pulley halves (2 ea.) 993 106 268 01 (Yellow, chromated color) *
Shim (0.5 mm) 964 106 268 31 (as required)
Shim (0.7 mm) 964 106 268 32 (as required)
* The ratio of 2.68 to 1 remains unchanged.

911 Carrera:
The new version pulleys an also be installed on the 911 Carrera. However, the previous version belt must be used.

Description Part Number
Previous belt (1 ea.) 999 192 343 50 (760 mm long)
When installing the new version pulley halves on the 911 Carrera and Turbo, the distance spacer, (see arrow, illustration) is machined as part of the new version pulley and is no longer required. Because of this, it is no longer possible to store adjustment shims behind the distance spacer on the outside of the alternator pulley. Shims removed during the tensioning procedure should be stored in the vehicle tool kit. The tensioning procedure can be found in Repair Group 13, page 13 - 32.

FotoVeloce

Geez this sounds complex. I suppose these parts are pretty pricy too. This is something I want to do since my belts look pretty old. I'm wondering how many spacers I might need to order, or to just reuse the spacers I currently have.

Thanks for posting this TSB!

geolab

its here

Mike J

Oh, I'm back.

This is my two cents worth but I would not do the update unless you have been having problems with your belts or they are very noisy. If they are shreding or wearing prematurely then do the update. I skipped the update and just went for the RS pulleys instead. That works for me but its not for everyone since charging is marginal if the car is idling. If you do a lot of stop and go then its not that great...but you should not be driving your p-car in stop and go traffic anyways.

Some people have had problems with the nut stripping on the alternator shaft...mine came off no problem so I have been lucky.

The update is not complex, you just remove the old parts and put on the new ones, new belts and go.

Cheers,

Mike.

ppressle

I may have a set of the pulleys available. I just bought the rs pulley hub and don't need both.

Pete

Dudley

Mike & G-L Thanks a lot.

I did a couple of searches but came up with nothing and now I see it was posted only a week ago! Sheesh!

I had the RS update but my idle dropped more than I was comfortable with.

jimbo3

What does the "old" style pulley look like? I have what I think is the updated version as it's sorta yellow as described in the TSB, but I want to be sure. Couldn't find a part # on it and not going to pull the pulley off just to check for it.

Also, I take it that the old size belt won't work?? I guess I need to double-check my spare belts to make sure I have compatible parts.

TIA
-Jim

ppressle

http://p-car.com/diy/vbelt/

From that site:
(8) For the alternator pulley the factory has an updated kit to prevent premature wear of the belt. The new part in the TSB is 993-106-268-01 and costs about $58.00USD with PCA discount. A new pair of shims are also listed in the bulletin so pick them up too (about $1.50 each). Shims are used to adjust the belt tension. The general rule of thumb to remember is: less is more (fewer shims is more tension) and vice versa. If you look at the pictures the newer pulleys are larger in diameter, have a slightly less curve, and have the spacers built in. Delete the old pulleys and spacers.

FotoVeloce

What is the advantage of the RS pully? Slower or faster fan spin or... ?

Thanks for all the killer info guys!

- David

ppressle

Don't know the official reasons, but
lighter, simpler, fewer moving parts, alternator spins a bit slower, so less drag.

chris walrod

and believe it or not, I did notice a small difference after installing mine. A little snappier

txhokie4life

Old thread -- but I threw a belt on my 96 993. So I'm doing the update.

A little confused. Why does it say the TSB has 2 shims (7mm & 5mm) but later it says to not use the existing shims (assuming it means nor new ones).

If you go with the 760mm belt you do not need the shims? Are they differentiating between the 993 and pre-964's (911)?

I ordered the extra shims -- and I have both a 957mm and 960mm belt.
I'd prefer to use the 960mm (as I have 2 of them) and I'd keep one as a spare.

thanks,

Mike

Mike J

The trick is to use the belt tension to judge the number of shims, do put it all together with what you think will work and see how tight the belts are. The proper way is to use a belt tension gauge but you can do it by feel too - moderate pressure to get about a 1/4 inch of flex.

Cheers

Mike

Top-Gun

I've got a brand new set of the updated pulley halves, bought them and discovered mine were already done.

If anyone needs them pm me and I'll save you a few bucks.