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Kraftday Kraftday is offline
Scottsdale Arizona USA
 
Join Date: Mar 2010
Location: Scottsdale, Arizona USA
Posts: 321
Garage
Thought I would check in after a while..I've missed the community! I recently moved on from my third tour of duty at Patrick MS. During my time there I dealt with thousands of clutches and have some experience to share that might be helpful.


Reading a good portion of everything going on with this but not the middle pages...
The few pictures I see but didn't see part numbers or summary? It can only be a certain number of things and hope your level of frustration isn't to the throwing wrenches stage. Hope this helps and apologies if I missed the part numbers to check!


Looking first to not original parts list:

1. My first thought is incorrect disc thickness. There are a few different thicknesses and part numbers to properly match with the pressure plate. ~10mm for most stock 76-89 (930/G50) and ~8 mm for (Sachs Performance).

The Sachs Performance (RUF 5 Speed Disc) PN: 88 1861 999 615 is thinner at ~8mm and designed to work with the matching pressure plate (RUF 5 Speed / 934), NOT any stock 76-88 pressure plate. If you have a HP pressure plate with a stock disc, that is a no go. It is really unlikely SACHS messed this up..they are really tight QC / ISO these days. In my experience these disc applications get messed up sometimes with parts vendors as the stock photos are sometimes showing wrong or older parts.

2. My second thought would be flywheel resurface. The pressure plate mounting surface and disc friction surface both need to be min cleanup cut..this is likely correct but worth mentioning. The flywheel has a machined groove near the outer bolt ring..this is an indicator of min thickness.

3. Third the other thing that sometimes happens with introduction of a new lower profile pressure plate is the limit pins can bind on the underside of the ring gear. The earlier ring gears (low profile) have 3 clearanced hole features. You have a MODE starter ring gear extension and release bearing extension. The ring gear extension features the same larger clearance holes so this is not the problem.

4. The other not so likely event is the damage of the pressure plate diaphragm due to over-stroking. Not likely but they can get tweaked.

Hope this is of constructive help!
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Old 06-09-2015, 03:52 PM
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