Helper Spring Not Helping (much) 82SC

chrispx · 03-14-2007, 03:44 PM

Greetings,

I've just replaced the clutch cable and helper spring. Everything went in just fine and the proper adjustments were made. However, when cycling the clutch the helper spring hangs up and does not come back all of the way so I lose the 1mm of free play at the throwout arm. I can manually push the spring/arm back into place and the free play returns. When it hangs, I don't think that it is exerting any force on the throwout bearing as the adjustment bolt is just lightly contacting the throwout arm and the arm has returned all the way to its resting point. If I disconnect the cable, the spring doesn't bind at all, it's only after I take up the slack that the issue arises. The good news is that the clutch pedal operates smoothly and feels much better with the new cable and spring installed.

Has anyone dealt with this before? What else should I check?

Chris

Superman · 03-14-2007, 04:00 PM

Interesting. I wonder if tightening the lock bolt a tad might do the trick. The little one. I know that sounds counterintuitive, but I believe it is the force of the pressure plate, pushing the little arm back, that forces the horseshoe spring to go "over the top" and whang back against its proper resting boss. that is, the pressure plate and the small arm should be forcing the horseshoe spring rearward, causing it to "cock."

jtfreels · 03-14-2007, 04:04 PM

A new helper spring? Did you build it up? If so it is possible to get it on backwards. The spring should be very hard to push back and it should "snap" into place almost hitting the exhaust.

Look at this thread Clutch Cable Failure??

for some good photos of the way it should be.

Jay

chrispx · 03-14-2007, 04:25 PM

Jay,

It's put together correctly. I took some video of the proceedings as I was taking it apart. Reviewing that, combined with the pictures from Bentleys, 101, and the tech article here made sure that I put it together right.
The clutch might be thin, I wonder if that is contributing to the problem?

jtfreels · 03-14-2007, 04:34 PM

Great. My problem was I could never get the full 25mm movement on the arm.
It was suggested to me that the throwout fork might be bad. Finally dropped the engine and that was it. Fork was cracked.
(my thread Son and Father engine drop)

BrokeMyCar · 04-03-2007, 11:37 PM

How did you check that you weren't getting the full 25mm on the arm? I'm experiencing similar problems (e.g. see pics at the bottom of http://forums.pelicanparts.com/porsche-911-technical-forum/337221-clutch-cable-investigation.html#post3177119 ) and wonder if I have the same problem...

jtfreels · 04-04-2007, 05:40 AM

In attempting to adjust the clutch, when pressing the pedal to the stop you should get the arm to move 25mm from the pedal full up to the pedal down to the stop. I was only getting 20mm, no matter what I did.
I've followed your other thread

, regarding the Omega (helper) spring, it should have been fairly hard to get it to go all the way back (near the muffler), was it. Should have been a "whang" and snap in to place. I'm wondering if your spring is weak. It is supposed to be over center and make it easier to press the pedal to get the clutch to work. I'm sure you've looked at it but the tech article on this at http://www.pelicanparts.com/techarticles/911_clutch_cable/911_clutch_cable.htm is very hepfull.

BrokeMyCar · 04-04-2007, 08:21 AM

Thanks!

No, the spring was super easy to move around, and no "whang" to speak of. I think I'll try pulling the spring to inspect bushings, then WD40 the heck out of it and see if that helps. Otherwise it looks like I'll be buying a used one (new ones aren't available anymore?!)

Babak

Gunter · Gunter's Garage

If all components are good and adjusted per the manuals like Bentley, it works fine.
If the C-spring is tired, it still works but the clutch pedal is harder to push.
The Bentley explains how to get the 25mm travel.
WD-40 is not a good lubricant.

BrokeMyCar · 04-04-2007, 08:49 AM

Thanks Gunter - the clutch pedal definitely isn't harder to push - it doesn't even return all the way! Based on some other posts I was thinking that perhaps some grit had gotten between the C-spring's leaflets and WD-40 could creep in there. Perhaps I should finish with a white lithium.

It's not looking good - we've ruled out:
-the roll pin at the pedal
-a weak or broken C-spring
-broken cable (even a stretched cable wouldn't do this, I think)
-the clutch return spring in the pedal cluster

I'm left with:
-a "jammed extended" C-spring
-one of the lever arms jumped a notch
-something in the bell housing (fork?)

Babak