Their instructions clearly indicate the setting for the timing belt to be 5.0 - 5.3 using the 9201 tension tool. How about the other 4 belts? Can the 9201 be used to set their tension as well? What should the readings be or where on-line can I go to find out?
Thank you,
Bob
 

The 9201 can't be used on the V-belts, but can be used on the poly-ribbed alternator drive belt. It goes unbelievably tight - 9.2 for a new belt, and
8.4-8.8 for a used belt.

The tension on the V-belts should allow 1/4" (0,5-1cm) deflection with firm thumb pressure in the center of the longest run.

The top and sides of the V-belts should be perfectly flat, the belts must not touch the bottom of the pulley, and there should be no cracks or missing chunks.

Wally Plumley
928 Specialists

==========

One possible reason for low voltage is a loose alternator belt.

The "10mm with thumb pressure" check given on page 13-18 applies to the V-belts used on earlier cars.

The flat poly-rib belts used on later cars should be adjusted using Porsche Special Tool 9201 per page 13-18b.

It is worth noting that the 32-valve timing belt is set to 5 on the 9201 gauge (in whatever units that might be), while the alternator belt is set to 8.4 - 9.2 of the same units. That is so tight that the belt feels like a solid bar.

Bottom line - if you don't have access to the 9201 gauge, tighten the flat poly-rib alternator belt as tight as you dare, then a little tighter than that.
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