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chickengod · Posted: Mon Jan 12, 2004 9:36 am Post subject: A clutch of woes

Hi,

Second post now

I recently had a problem with my clutch (1983 924NA).
I was in Tesco's car park, reversed out of parking space, foot on clutch to shift into first and the pedal goes totaly dead(still sprung but no resistance), cannot move!

I thought it was the clutch cable breaking so I got a tow home and ordered a cable. This was before christmass so its only just come. The clutch cable came after two weeks and I went out to fit it. Bugger, the origional cable is fine, serves me right for not looking. I replaced the cable anyway adjusted it and had the same problem (slack pedel with no resistance).

I was starting to get worried at this point, clutch ---> expensive. I got under the car, removed the clutch inspection plate and after poking around found that the thrust bearing had uncliped from one side of the pivot arms and had twisted around a little. The thrust bearing was pushing against the spring diaframe but only one side so not really doing a lot ! I used a long flat screwdriver to turn the bearing around to where it should be and clipped it back on. On my back using two screwdrivers and a torch in my mouth + lots of swearing. The clutch works agian

.

There is a problem with gear shifts now. If I start the car with my foot on the clutch, I can shift into any gear with ease. Now the problem, when I take my foot off the clutch pedel, press down again and try to shift into first or reverse, I cannot. I can shift into the other gears but second is always a bit stiff. If I start the car with my foot off the clutch I cannot shift into first or reverse. The gearshifts are ok once I am moving and seem to be ok and junctions etc. The problem seems to be just from starting.

Anybody have any ideas. Clutch is fine, no slipping. Gearbox about to collapse and die ??

Smoothie · Posted: Mon Jan 12, 2004 10:25 am Post subject:

Did you re-adjust the clutch after clipping the bearing back in place?
_________________
"..it's made in Germany. You know the Germans always make good stuff."

'82 924T, US version, dark green metallic, 5 speed Audi 016G gearbox

chickengod · Posted: Mon Jan 12, 2004 10:36 pm Post subject:

Yes, I adjusted the clutch after recliping the bearing with the bearing pushed up against the diaframe. The bearing was not pushed up hard just resting against.

I don't know much about gearboxes but it sounds like some problem with the driveshaft spining - dont know

-nick · Joined: 16 Nov 2002 Posts: 2699 Location: Cambridge, MA

That's some pretty nice Macgyver work there

I think you're on the right track- it sounds like the driveshaft isn't decoupling entirely from the engine when the clutch is depressed. This keeps your driveshaft spinning a bit too quickly for the syncro's to help the gear engage. Since you've already adjusted the clutch, the only thing left is bad news- likely the pilot bearing is going.

Do you hear any noises anytime during the engaging process- grinding/rattling/bad bearing? If the throw-out bearing was cocked, then it could have transmitted some stress onto the pilot- which is not very hefty.

Just some food for thought. If it's the pilot, then suddenly not being able to engage any gear is in the future.

This is probably worst-case. If you're not hearing any noises then you can look elsewhere.

-nick

kaffine · Joined: 13 Jun 2003 Posts: 644 Location: Las Vegas

Have someone hold the clutch pedal down and try to spin the torque tube shaft through the opening on the trans. You can also look to see if there is clearence between the clutch disc and pressure plate.
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chickengod · Posted: Tue Jan 13, 2004 8:00 am Post subject:

No noises when engaging clutch and I can just about change gear, from standing still, when the gearbox has warmed up a bit.

Another thing just happened today. Got in the car and the seat tippd back on me !! Had a look and one of the runners has pulled out of the floor, right at the bolt. I now have a hole in the floor. Looks like a welding job

Things always come in three's. I wonder what the next is.

chickengod · Posted: Sat Jan 17, 2004 10:10 am Post subject:

Thanks for replies.

I am going to try adjusting the clutch again with my fingers crossed.
The last time I made all the adjustments on the cable, I think I should have done it by moving the arm on the clutch bellhousing. How do you loosen the arm? The picture in the manual just shows a bolt that holds the lever on a tube. Do you remove the lever completely and then reattach? It looks like the end of the tube has grooves on.

Found somebody with a MIG welder, they are going to weld two small plates of metal where the seat bolts go. Strange, there is no corrosion at all in the floor.

Cheers
Iain

Joes924Racer · Posted: Sat Jan 17, 2004 10:27 am Post subject:

I strted that way first it was a weared out friction disc just slipped
after I replaced it. The nylon cable end broke. Aftern that When it
came time to do the friction disc again I thru in a new thrust bearing.
Id check the cable adjustment. I had it go to where Im cussen silly
cause I couldnt get it right. I only add this as your bearing got a
good thrashen.
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1979 porsche 924 Na
1980 porsche Turbo 931GT Replica
Have u ever driven a turbo.

chickengod · Posted: Sat Jan 17, 2004 10:46 am Post subject:

I think the thrust bearing is ok - looks and feels ok anyway.

When the bearing twisted off the pivot arms I stopped using the car so it should, and anything it came into contact with, be ok ------ I hope.

Iain

924RACR · Posted: Sun Jan 18, 2004 12:33 am Post subject:

I suppose it's conceivable that the tube on which the TO bearing slides is bent and sticking a bit... dunno...
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dpw928 · Joined: 02 Nov 2002 Posts: 1860 Location: owasso, ok 74055

The throwout bearing being misaligned could have worn the fingers on the pressure plate so the bearing won't completely release the clutch. This happened on my 80 and I went through two pressure plates before I realized one ear was miswelded on the fork.

Dennis
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chickengod · Posted: Tue Jan 27, 2004 8:11 am Post subject:

Thanks for all the replies to my question.

Fixed it

I tried adjusting the clutch again but this time I spayed some dry-lube on a small artist paintbrush and lubricated the thrust bearing sleeve. I can now get it into first and reverse when standing and cold.

Somebody might want to try this if they ever have the same problem. Let the clutch cable right back down and move the thrust bearing back away from the clutch, then grease the tube the thrust bearing runs (not to much, you don't want it on the clutch plate).

Iain