Clutch gurus unite.. Clutch switch doesn't activate, no more adjustment..

[HFR_Racer]

Vehicle info: 1986 Carrera Targa w/ 915 transmission

Recently I adjusted the clutch cable at the transmission according to Wayne's book and the Haynes manual. I immediately noticed improved clutch feel and shifting.

Problem: After the clutch adjustment I my cruise control became inoperative.

Root cause: My clutch swith isn't activated when the clutch pedal is in the normal (non-depressed) position.

Attempt to fix the problem:

1) I adjusted the clutch switch forward as much as the slots in the bracket will allow and the clutch switch still isn't far enough forward.

Ideas on how to fix this problem:

1) Increase the slots on the switch bracket which would allow me to move the switch further forward.

2) Adjust the clutch cable clevis where is attaches to the clutch pedal linkage to bring the clutch pedal toward the drivers seat thus making the switch.

I like idea #2.. Will this work? Is this the correct solution?

I've attached a photo of my current condition so you can see how much free play I have (dimension A) and you can see the clutch switch lever (item B). Notice how far forward my clutch pedal is normally.. Maybe this isn't correct???




Thank you,
HFR_Racer

[jtfreels]

I've had that view for several hours in the last week (and the under the engine view) Hopefully I'll be putting in my pedal cluster this evening so I'll do a comparison.

Jay

[john walker's workshop]

bending the switch arm more, is one way to fix it. you could adjust the sheath nuts on the cable below the trans to raise the pedal more. that's what that adjustment does, but it would also raise your engagement point.

[HFR_Racer]

In reply to John..

It looks like bending the switch arm won't help the situation since I need to gain at least 1/16". Maybe straightening the bend in the switch bracket would help but if I take the bracket out I might as well put it in the mill and increase the length of the slots in the bracket.

I've adjusted the nuts under the transmission based on the clutch cable adjustment instructions. The clutch feels great so I'd rather not mess that up. Maybe the issue it that my clutch cable is stretched too much. The clutch cable works well so I hate to replace it if there is another sensible fix.

John:

What don't you like about option #2? I'm curious since you are highly regarded on this thread.

Thank you,
HFR_Racer

[john walker's workshop]

#2, adjusting the front clevis farther onto the cable is the same as adjustig the sheath nuts at the trans bracket. both would bring the pedal up more. the cable should protrude into the clevis about 1/8" anyway. any more it will contact the pull lever. you might try adjusting the bolt a bit more to close up some clearance between the long and short lever. you just need a bit of detectable clearance, not the rather large amount the book calls for. that will bring the pedal up too. pry the arms apart lightly with a screwdriver first to get a true feeling for the clearance.

[HFR_Racer]

Thanks John..

I'll check it out....

[HFR_Racer]

I took your advice John and this is my current condition (see photos).

The sleeve nuts are adjusted to the maximum condition to pull the pedal back toward the driver seat. This leaves no clearance between the small and large clutch actuation arms on the transmission. The clutch switch still doesn't make up, but it's very close now....





Does this mean that my clutch cable has stretched too much to be adjusted further and need replaced? Let me know..

I'm interested in the following options:

1) Adjust the clutch cable clevis a bit at the clutch pedal to effectively shorten the clutch cable.

2) Increase the slot size in the clutch switch bracket so I can move the switch forward.

3) Or both options together since I've got it apart


NOTE: My cruise control worked (which means the switch was making) prior to a recent engine removal. Not sure what might have changed other than adjusting the clutch cable. Maybe I'm looking in the wrong place?

[jtfreels]

It looks to me that your helper spring is not in position. It should be under tension and should be almost touching the exhaust pipe.
Look at the image in this thread re-attaching clutch helper spring and lever?

and compare with yours.

At least this is how my SC is.

Jay

[john walker's workshop]

notice the zero clearance between the long and short arms. you have run out of adjustment there because the clutch is over with. basically a disc down to the rivets. i assume you adjusted clearance there first, with the cable sheath adjustment slacked off. a very stiff pedal usually accompanies this problem. either that or you did the adjustment wrong.

[jtfreels]

John,

Am I wrong on the helper spring?

[john walker's workshop]

that too. the pin that sticks up from where the horseshoe spring pivots needs to contact the angled stop which can be seen at the top right corner of that picture. it's way off. so you need to do the adjustment procedure properly first. disconnect the cable hook from the arm first and then set the clearance between the arms with the bolt.

[jtfreels]

Thanks John ( sorry to hijack HFR_Racer, but...)
From memory my stop does not stick up as far as this one. Could it be broken off, is that a huge problem.
I seem to remember in reading a post were its not unheard of form it to be broken.

Jay

[john walker's workshop]

the stops do break the lip off occasionally, which would tend to keep pressure on the short arm when the pedal is released.

be sure the long arm swings freely on it's shaft. they can get pretty stuck from rust/corrosion/crud that it's hard to get a good feel for the freeplay between the arms. once that's set, loosen the sleeve nuts and pull the cable sleeve free of it's bracket. stick a screwdriver in the loop and pull back hard to lift the pedal up. keep the cable pulled out and loop it onto the hook on the long arm. then reposition the two nuts and set the sleeve back into the bracket. adjust the nuts again so when it's correct, the cable does not pull the long arm off it's stop. you should be able to push the inner cable and it's boot sideways about 1/2" between bracket and long arm when it's right. the pedal will be up then hopefully.

[jtfreels]

Thanks John, hopefully HFR_Racer has benefited as well!
I just need to get the pedals built and back in the car and then I'll attack the trans end.

Thanks

Jay

[HFR_Racer]

John:

I know the second set of pics show the clutch incorrectly adjusted. I just set this up to show that even when I adjust the sleeve nuts to the extreme end that the clutch pedal still doesn't come back enough to make the clutch switch.

I'll try re-adjusting on Sunday morning using the proper procedure and then I plan to relocate the clutch switch a bit.

I'll let you know how it goes.

Thank you,
HFR_Racer.

p.s. The car only has 60k miles and the clutch doesn't slip a bit. I can't believe that the disk is bad.

[HFR_Racer]

John:

Your advice was rite on point..

be sure the long arm swings freely on it's shaft.

I found that the long arm was partially frozen to the main shaft coming out of the transmission. I had to use a 2 jaw puller to remove it form the shaft. Thus I couldn't get the 1.2mm gap setting consistently between the long arm and the short arm. I cleaned it all up, adjusted the clutch correctly and everything came out as expected. The clutch pedal is full back toward the driver, the helper spring is in the correct position and I have a gap between the long and short arms.

Thank you for leading me in the rite direction. Thank god I didn't have to remove the clutch switch. It looks like a pain to get to the wires .

Here is a photo of what I have now: