Clutch Adjustment Mystery

gerry100 · 09-08-2003, 04:39 PM

Iv'e been posting on this forum for about 24hrs now trying to get thorugh my first DIY clutch adjustment, I've got some good hints and tried them with no results - but I do have a theory.

My problem is that I can't get the recommended 1.2mm clearance between the small and large arms ( cable disconnected). With the screw backed completely out an out of play there is only about 1/2mm between the arms. Prying them apart with the BFSD doesn't work.

I think that the Previous owners mechanic reinstalled the small arm in the wrong angular postion on the shaft when the clutch was replaced 22K miles ago, effectively eliminating most of the available clearance. My wrench commented that it was a little bit off down there but I never followed up on it.

To remove the small arm and reposition it back form the large arm about 10deg would allow for adjustment and clearance. I've also noticed that the the coil spring appears a little overextended. Helper(horseshoe) spring appears in correctly, but I'm not sure.

Is taking the small lever off and remounting it back 10deg or so as easy as it looks?

Does this make mechanical sense/ ( I'm not sure what the small lever arm does)

Is there a reference measurement that dictates the position of this arm when it is installed?

Help appreciated.

Tyson Schmidt · 09-08-2003, 09:08 PM

Yes, it's as easy as it looks. But I'm really not sure why you are having this problem. The only time I've seen this issue was on a 930 with a non-standard clutch and pressure plate.

If the disc were severly worn, it would make sense. But if it's that new, then it doesn't figure.

The next question is whether you will have a long enough adjuster bolt to reach the small arm when you reindex it.

ChrisL · 09-09-2003, 01:02 AM

It's very easy -- just take off the circlip, unclip the return spring and slide off the lever. It too tried moving it and found there is only one obvious position for it. Moving it one spline either clockwise or counterclockwise took it too far out of whack.

Chris.

gerry100 · 09-09-2003, 03:14 AM

I'll try moving it an amount that allows room for the adjustment bolt. I'm sure the bolt will be long enough, now the bolt ( head and nut on same side, doesn't even go through the lever arm before reducing the 1/2mm I've got.

Thanks guys.

Superman · 09-09-2003, 06:40 AM

Again, that large arm needs to be pried in the opposite direction that the cable pulls it, until the horseshoe spring goes 'over the top.' If you have an exhaust system like the stock '83 system, where a crossover pipe runs across the bottom of the engine near these parts, then the large arm actuall gets pried rearward until it WHANGS against that crossover pipe. Then install the small arm, the cable and adjust.

gerry100 · 09-09-2003, 06:51 AM

Hmmm, I 'll try "whanging" the large arm against the Xover before I fool with the small arm. I've been a little tentative with tyhe BFSD .

Am I to assume that the large arm should rest against the Xover pipe in the normal position? I believe I have > 1/2inch gap.

If the gap doesn't improve after the whanging then I'll try the small arm.

I've been assuming that the large arm and horseshoe spring would not need prying since nothing has been disassembled.

Thanks again.

john walker's workshop · 09-09-2003, 06:54 AM

the arms generally get real close together only when the disc worn out. (real thin). be sure the cable itself is slacked off enough so the long arm can rest on it's stop, before adjusting the clearance between the arms.

gerry100 · 09-09-2003, 07:42 AM

cable is disconnected, I hope the clutch with 22k miles is not thin ( I don't know the quaity work done for the Previous owner).

Where/what is the stop for the long arm?

BTW - car is an '86 3.2 Carrera

Superman · 09-09-2003, 08:07 AM

22k miles is young for a clutch disk, or at least it should be. Now pry that large arm back away from the cable, as far as it will go. The horseshoe spring will fight you at first, and then go 'over the top' and press the arm against its stop.

john walker's workshop · 09-09-2003, 08:07 AM

at the end of the long arm is a pin pointing upward that the horseshoe spring pivots on. that pin butts up onto a stop which is on an aluminum bracket bolted to the side of the trans. the bracket is also the pivot for the open end of the spring. there's a 90° L shaped steel stop screwed onto the aluminum bracket that the pin contacts. it's missing sometimes.

Jdub · 09:42 AM

a 1977, right?

Keep in mind that the arm on the shaft probably has a pin locating it to the shaft (this done up to about '78 model). Look hard for a small circle about halfway up the lever arm on the shaft. Drive this out with a pin tool.

John

EDIT: Whoops, wrong lever (see John's post below). You are going to need to reset the smaller lever, not the Lever Major I am speaking of. Allthesame, do remember that darn pin!

john walker's workshop · 09-09-2003, 09:30 AM

why take that arm off? just the small one MIGHT need to be rekeyed, but it will probably be too much or too little.

gerry100 · 09-09-2003, 04:37 PM

well guys-

- the helper spring is snug against the heat exchanger

- cable disconnected

- you're right, indexing the small arm even one spline is way too much.

- I'm back where I started, about 1/2mm clearance.

- Is my 22k miles clutch toast?

( FYI, I 've driving a stick for 36yrs, a 915 Porsche for 2, don't do hard starts. shift gently, Could 4 DE days with semi competent Heel/toes have done this?I didn't notice the slight slippage that prompted the adjust attempt until at least 300 miles after the DE)

Thanks for any more ideas or condolences. You've all been helpful

john walker's workshop · 09-09-2003, 05:03 PM

the spring being snug against the exchanger could cause the long arm not to contact the stop, which might relate to the lack of clearance. so is the pin against the stop? sometimes the exchanger needs the clawhammer massage for spring clearance.

gerry100 · 09-09-2003, 05:52 PM

When I say snug, I really mean very close but not touching and where I think it should be form all the pix I've seen.

I don't think the helper is in backwards, but is there any way to tell?

gerry100 · 09-09-2003, 05:55 PM

Oh yea, I'll take another look at the spring and the stop. Its tough fopr me to get a good look as I'm workin w jackstands in my garage.

gerry100 · 09-16-2003, 08:57 AM

Mystery solved.

Finally took it in to my mechanic, reviewed paperwork from the previous owners shop, and had him look into it.

Apparently, when the bearing release fork was replaced 11k miles ago it was installed in the wrong angular position on the shaft which resulted in the small arm being up too close against the large arm.

Anyway, he reindexed the small arm and used a longer adjustment bolt to adjust the clutch. Longer term, we'll reinstall the release fork when the tranny is out for another reason.

Othere wise my clutch ( and wallet ) are fine (for now).

Thanks for everybodys help and I hope the topic adds to the knowledge pool that we all wade in.