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Posted by: scruz914 Dec 6 2004, 10:40 PM

Symptom: I push in the clutch, start the engine, try to engage reverse. Grinding!
Also happens while driving even after going through the gears with clutch pedal in (past experience has shown that this "stops" rotating gears).
Recent activity (in order): Tightened clutch cable because it was too loose (i.e. not related to Rennshift install), installed Rennshift Jr., adjusted shift rod.

What I cannot figure out is why the reverse gears are spinning when I start the engine with the clutch pedal fully depressed. After I tightened the clutch cable the clutch engages after about 2 inches of pedal release. I can engage 2 - 5 without any grinding. About 50% of the time 1st gear grinds under the same conditions.

I have played with tightening and loosening the clutch cable without a change. It appears that the problem is only with the far "left" gears, i.e 1st and reverse. Can this be due to inproper shift rod alignment?

I have adjusted many VW clutch cables and the 914 does not seem to be any different (except the 11mm nuts, where did that come from?). The clutch cable tube appears to be firmly in place. It does not move within the tunnel and there is no wiggle where it comes out of the tunnel.

-Jeff

Posted by: Ctrout Dec 6 2004, 10:47 PM

Mine did this pretty badly until I replaced my linkage bushings. The one at the trans was pretty much non-existant. It helped a lot but I still grind badly when downshifting 3-2 but only when cold. That one still has me stumped.

Posted by: scruz914 Dec 6 2004, 11:15 PM

Interesting. I just looked at the PO's maintenance notes. There is an entry for reparing the clutch tube, prior to that there was replacement of all of the clutch pieces, but no mention of linkage bushings.

The thing I cannot grasp is why, when the clutch is fully disengaged prior to starting the engine, parts of the transmission are spinning after the engine is running? It is almost like a ghost is turning the tranny while the clutch pedal is fully in. Does slop in the bushings allow for engagement of the clutch to the tranny?

I'll check out the bushings.

Posted by: Aaron Cox Dec 6 2004, 11:19 PM

pivot arm? shims?

Posted by: bondo Dec 6 2004, 11:27 PM

It could also be a failing pilot bearing. My wife's subaru had those symptoms, eventually it got so bad that when you started the car in gear with the clutch in, it was like the clutch wasn't depressed at all, like you were starting it in gear. Pulled the engine, and found a pile of half-spheres where the pilot bearing should have been.

Posted by: scruz914 Dec 6 2004, 11:37 PM

I am guessing the pilot bearing is IN the tranny. A too loose pilot bearing will cause the gears to spin? I have so much to learn about transmissions. In all of my years of working on cars I have avoided transmissions. Sounds like I'll be in for a transmission repair sometime soon.

Posted by: James Adams Dec 7 2004, 07:02 AM

What about the clutch pedal stop on the pedal board? Here is the complete adjustment procedure:

Clutch Pedal Freeplay:
Clutch pedal free play is 15 - 20 mm (approx. 3/4 in. ). Free play is measured by pulling the pedal to the rear of the car (pulling the pedal toward you - opposite most cars).

Checking Clutch Pedal Travel:
The pedal travel check should be made with the transmission warm. When the clutch pedal is depressed to the stop, reverse gear should engage without gear clash.
1. Remove rubber mat.
2. Loosen both pedal stop retaining bolts.
3. Slide the pedal stop up or down until reverse can be engaged without gear clash
4. Tighten retaining bolts. Re-check pedal travel.

Posted by: ClayPerrine Dec 7 2004, 08:15 AM

The pilot bearing is in the rear of the crankshaft. It holds the input shaft aligned with the crankshaft, and allows the input shaft to stop even with the cranks spinning.
It's not internal to the transmission,and should be replaced with every clutch job.

Posted by: jwalters Dec 7 2004, 08:19 AM

I agree, sounds too much like a failed pilot bearing------tho could be amplifying problems as well, such as broken clutch fingers---

Your mystery will reveal itself when you take that tranny out..........

Hint> when you replace the pilot bearing--do not slather it in grease---only a fine coating on the bearing itself---or else centrifugal force will sling the grease out and it will land on your clutch facing, which will forever make it not right!!!!
Good luck!

Posted by: scruz914 Dec 7 2004, 09:42 AM

Thanks everyone for your responses. I think the first thing I will do is to pull the pedal cluster and make sure everything is good. Two reasons for this are: its is easier than pulling the tranny and to my knowledge the pedal cluster had not been serviced by the PO. I know that the clutch was serviced just before I bought the car but do not know to what extend other components were replaced. I will plan on pulling the tranny in the near future.

James, That Rennshift Jr. has to be one of the best upgrades to make on a 914! Thanks for putting it together for me.

-Jeff

Posted by: DJsRepS Dec 8 2004, 05:44 AM

On my poor car prior to clutch job the trany seal leaked grease all over the disk. It would not fully disengauge at any adjustment it kept the gears spinning I had to slide it into 3rd gear (Good seco ring) to stop the spinning to quickly put into 1st. Then with proper free play in pedal it would slip if really pushing it what a tired 1.7 can push it.... If it is a pilot bearing, with the clutch engauged every thing turns together the pilot bearing can not make any noise or malfunctions at that point. Any noise at that point is esleware in the drive train.


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