924Board.org

datatrain · Posted: Sat Jul 10, 2010 7:06 am Post subject: Clutch Adjustment still AGAIN

After numerous attempts at this I tried again........

I've followed the instructions to set a 1/4" clearance on the pedal. I had a helper that checked it as I slowly turned down the top adjusting nut to reduce the clearance.

when I stopped and locked both nuts, the pedal felt OK and it had the required clearance but a road test showed me the clutch grab point was still at the top of the pedal.

I'd REALLY like it to grab about 1/2 way up from the floor. I don't know how I can change that without loosing the pedal clearance. Perhaps I simply don't understand the mechanism but it seems very simple.

Maybe a set of idiots instructions is what I need.

This all started when I replaced broken ends on the clutch cable in January.

Suggestions anyone ?
_________________
'78 924 NA with Collector plate
33 year old car, with me for 21 yrs
Mint '92 318i BMW
Near mint '98 Buick LeSabre
VE7HFR

!tom · Posted: Sat Jul 10, 2010 9:36 am Post subject:

Is your clutch worn out?
_________________
78 924 NA
5-lug

datatrain · Posted: Sat Jul 10, 2010 9:41 am Post subject:

I don't think so. It worked fine until the cable broke. It doesn't slip or grab or exhibit any signs of fatigue. AND it's still original with only 123,000 miles on it.
_________________
'78 924 NA with Collector plate
33 year old car, with me for 21 yrs
Mint '92 318i BMW
Near mint '98 Buick LeSabre
VE7HFR

Smoothie · Posted: Sat Jul 10, 2010 11:39 am Post subject:

No firsthand experience with adjusting the 924 cabled clutch, but having read several threads on it here it
seems that most/all don't follow the FSM/Haynes specs to a T.
To slacken the cable some and move the engagement point down, apparently you need to loosen nut "L"
and move it up some (allows the outer cable ("J", "K", "N") to move down), then re-tighten nut "M"..

_________________
"..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

datatrain · Posted: Sat Jul 10, 2010 1:47 pm Post subject:

That's exactly the reverse of what I've been doing. I tighten nut "L" and it pulls the clutch arm upward to shorten the travel to engage the release bearing.

Now there is a project for Monday morning. I'll try the opposite and see if I get the desired result.

I did find tho that I had far too much clearance when "L" was too loose.
_________________
'78 924 NA with Collector plate
33 year old car, with me for 21 yrs
Mint '92 318i BMW
Near mint '98 Buick LeSabre
VE7HFR

Slam · Posted: Tue Jul 13, 2010 5:22 am Post subject:

Sometimes the easiest and fastest method is to loosen both locknuts, lift the arm until you can hear/feel the TO bearing engage and then spin the top locknut down onto the bracket, locking with the nut underneath. Failing that, it's car-on-jackstands time and the first adjustment is made through the window in the bellhousing. The fun aspect of that is finding out the arm itself needs to be adjusted, but try the above and see how you make out.

HTH!
_________________
'88 944 Auto - may or may not resurrect

datatrain · Posted: Tue Jul 13, 2010 5:34 am Post subject:

Hey I like the sound of that method.

I was girding myself for the jack it up and measure the lever to bracket with the cable off and then try to adjust the arm. I was expecting the cinch bolt to be next to impossibke to get undone. A quick measurement with all the stuff in the way , indicated the distance was slightly over the 138mm +- 2 prescribed in Haynes.

I'll give this a try.
_________________
'78 924 NA with Collector plate
33 year old car, with me for 21 yrs
Mint '92 318i BMW
Near mint '98 Buick LeSabre
VE7HFR

datatrain · Posted: Wed Jul 14, 2010 4:57 am Post subject: Now I know why.

It looks like I need to do it the hard way. Slacking the cable and pulling up the lever to the bearing contact point will exacerbate the problem I think.

With all the stuff out of the way I measured from the lever to bracket and found over 158 mm (6 1/4") with the clutch adjusted now. Should be 5.43" before adjustment. I guess that accounts for the lack of pick up point adjustment. Guess I'll live with it until I'm in the mood to climb under and wrestle with it. Unless there is a secret work around I'm not party to.
_________________
'78 924 NA with Collector plate
33 year old car, with me for 21 yrs
Mint '92 318i BMW
Near mint '98 Buick LeSabre
VE7HFR

dpw928 · Joined: 02 Nov 2002 Posts: 1860 Location: owasso, ok 74055

Sounds like you are missing the second step of the adjustment. After you set the proper cable length, loosen the nut (V on above chart) so the lever (T) will move freely, push the throwout bearing to the pressure plate, then tighten the nut. This sets the lever to the proper angle.

Dennis
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81 931 5 sp
78 928 5 sp Silver
78 928 AT Euro Black

gohim · Joined: 02 Nov 2002 Posts: 4459 Location: Rialto, CA

Your problem is that you're trying to make the clutch work in a way that the designers of the clutch didn't design it to work.

The clutch is designed to start engage up near the top after a short freeplay, and from your description, that's what it does.

If you set it up to start engaging (disconnecting the transmission from the engine) at half of pedal movement, you may not have enough pedal travel to fully disengage the transmission.

I've owned 924 since 1981, and the only adjustment I've ever made to the clutch have been under the hood. I simply pull the cable up to judge the clearance, and turn the nuts to set the freeplay at 1/4".

I don't monkey around at the pedal or at the transmission, and the clutch works fine.

D Hook · Joined: 02 Nov 2002 Posts: 3158 Location: Omaha, NE

Rich H · Posted: Thu Jul 15, 2010 5:52 am Post subject:

What they said above, undo lock nuts, pull cable up run top nut down, tighten lower nut, drive.
_________________
1994 Lotus Esprit S4 - Work in progress...
1980 Porsche 924 S2 DITC Turbo - Original spec
1978 Homo-Sapiens - Tired spec
1953 Landrover S1 - Pensioner Spec

Slam · Posted: Thu Jul 15, 2010 6:08 am Post subject:

It IS possible to adjust the arm - just ask the guy who removed it to do a bellhousing build...

The trick is to get the bolt out, slide the arm so it can be rotated in the detent for the pinch bolt and then push it back onto the splines. Not really a fun way to spend your time.
_________________
'88 944 Auto - may or may not resurrect

D Hook · Joined: 02 Nov 2002 Posts: 3158 Location: Omaha, NE

Good to know. We never tried because it looked like there wasn't enough room but glad to know it's possible, if ever needed.
_________________
'80 924 n/a SOLD

datatrain · Posted: Thu Jul 15, 2010 1:43 pm Post subject:

Thanx all, I think I'll just accept gohim's advice that it works the way it was designed and be satisfied with that.

I guess the fact my daily driver is a BMW 5 speed with a hydraulic clutch has made me forget how the 924 was for the past 20 years. The travel distances are totally different and I guess more time in the 924 is warranted.

DAve
_________________
'78 924 NA with Collector plate
33 year old car, with me for 21 yrs
Mint '92 318i BMW
Near mint '98 Buick LeSabre
VE7HFR