Pelican Parts
Parts Catalog Accessories Catalog How To Articles Tech Forums
Call Pelican Parts at 888-280-7799
Shopping Cart Cart | Project List | Order Status | Help



Go Back   Pelican Parts Forums > Porsche Forums > Porsche 911 Technical Forum


Reply
 
LinkBack Thread Tools Rate Thread
Author
Thread Post New Thread    Reply
Registered
 
Join Date: Oct 2009
Location: Sonoma, CA
Posts: 576
Garage
What's wrong with this picture? Clutch helper spring

After my clutch pedal slammed to the floor (clutch cable and helper spring), I finally found the time to get almost everything back together. However, I'm perplexed about the situation. After attaching the big arm w/helper spring and the small arm, it seems the gap between the small arm and the adjustment screw on the big arm is either too large or too small, depending on how the small arm is installed on the spline. Here's a pic of the gap that looks too big.

When I remove the small arm, rotate it on the spline, and reinstall it so the gap is smaller, there is absolutely no room to get a feeler gauge between the small arm and the screw, even when the screw is backed all the way out. What am I doing wrong?


__________________
1983 SC
Blog
Old 10-21-2010, 09:46 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)
Registered
 
Walt Fricke's Avatar
 
Join Date: May 2004
Location: Boulder, Colorado
Posts: 7,275
Try it with the lock nut on the other side.

Or, did you pry on the harp spring to make sure it is snapped in the "clutch is engaged" position, ready to help disengage it?
Old 10-21-2010, 10:21 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #2 (permalink)
Now in 993 land ...
 
aigel's Avatar
 
Join Date: Mar 2003
Location: L.A.-> SF Bay Area
Posts: 14,885
Garage
Quote:
Originally Posted by Walt Fricke View Post
Try it with the lock nut on the other side.
Bingo!



George
__________________
97 993
81 SC (sold)
Old 10-21-2010, 10:49 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #3 (permalink)
Registered
 
Join Date: Oct 2009
Location: Sonoma, CA
Posts: 576
Garage
Now that's interesting. After reading your post, I looked more closely at the photos in 101 projects and the pelican tech article. I don't know why that lock nut is on the wrong side. Thanks for pointing that out. And yes, I snapped the spring into place.
__________________
1983 SC
Blog
Old 10-21-2010, 10:53 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)
Registered
 
Walt Fricke's Avatar
 
Join Date: May 2004
Location: Boulder, Colorado
Posts: 7,275
Well, let us know if moving the nut, repositioning the short arm, adjusting, and hooking up the cable got you your clutch back.
Old 10-21-2010, 10:57 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #5 (permalink)
Registered
 
Join Date: Oct 2009
Location: Sonoma, CA
Posts: 576
Garage
Well, looks like I'm more or less in the same spot. The first photo below shows the small arm at one position on the spline. The small arm is pulled back from the large arm as much as it can be. (I pulled it back with my hand, maybe 10-20 degrees.)

The second photo shows the small arm in another position on the spline; that is, I pulled it off the spline, rotated it to the next notch, and pushed it on. The photo shows the small arm overlapping the lock nut. The small arm won't go all the way on the spline.

I'm thinking I should either be able to move something a little to get some clearance between the small arm and the lock nut or that something is out of whack inside the bell housing.





__________________
1983 SC
Blog
Old 10-21-2010, 11:49 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #6 (permalink)
 
Registered
 
Join Date: Dec 2009
Posts: 825
why did pedal go to floor? cable broke ? check cable pin at front cross shaft under floorboard in tunnel to see if bushing and pin worn cutting thru arm
Old 10-22-2010, 12:33 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #7 (permalink)
Registered
 
Join Date: Oct 2009
Location: Sonoma, CA
Posts: 576
Garage
At this point I don't know what caused the pedal to go to the floor. In the thread I referenced in the original post, people had suggested a number of possible issues. I'm trying to eliminate the possible external causes before digging in deeper.

The cable looks fine, almost new, and appears to be the same length as a new cable. I replaced it anyway. The PO had replaced the pedal box bushings. I removed the pedal box and checked the roll pin and the arm the front part of the clutch cable attaches too. Both are in great shape. I replaced the roll pin and kept the rest. The helper spring looked fine, but I replaced it anyway.

Now I'd like to get everything adjusted in the ballpark so I can see if I have a clutch.
__________________
1983 SC
Blog
Old 10-22-2010, 06:53 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #8 (permalink)
Registered
 
Walt Fricke's Avatar
 
Join Date: May 2004
Location: Boulder, Colorado
Posts: 7,275
So what happens if you use spline position B (2d photo in your last post), with the nut on the bolt-head side so you can retract the bolt as far as possible? It isn't normal for things to be quite like that, but the proper feeler gap isn't the key right now. The key is why did the pedal go to the floor.

Not the roll pin, not the cable, not the harp spring (most likely as to the last two - a bad cable should show up as a few broken strands at one end or the other, or maybe where it emerges from the chassis. I think maybe the harp springs break the piece which is sandwiched between the inner and outer pieces. Should be able to see it, but it is not glaringly obvious.)

So just getting the levers to work at all will let you see if you can operate the clutch. If you can't get it to release, you know you are in for a tougher job. Adjusting the release to factory spec is secondary at this point.

Hint for the future: before removing the short arm (when you have things working right), put punch marks or file grooves on the arm and on the splined shaft end which line up with each other. That way you can always put the short arm back on in the same position. Saves time, and will allow you to differentiate between troubles with the TOB/fork/disk/pressure plate on the one hand, and the pedal/lever/cable system on the other hand.

Since you have had the pedal cluster out, can one assume that the bushing in the cable arm which holds the cable pin is OK? Don't think that would account for "to the floor," but just thinking of what might happen where.
Old 10-22-2010, 08:02 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #9 (permalink)
Ova Day
 
msterling's Avatar
 
Join Date: Jul 2004
Location: Wadsworth, OH
Posts: 790
Garage
If not cable, not pin in pedal cluster, not springs then maybe it is the clutch release fork. Was there any forewarning? Did the clutch adjustment seem to be drifting?
__________________
88 Triple Black 911 Carrera Cab, ex Garage Queen
05 BMW E46 M3
21 Tesla Model 3 LR
08 BMW 328xi
15 Ford F150
Old 10-22-2010, 08:53 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #10 (permalink)
Registered
 
vash's Avatar
 
Join Date: Sep 2003
Location: in my mind.
Posts: 31,823
Garage
Send a message via AIM to vash
the nut was on the correct side.

rotate the arm one spline over?
__________________
poof! gone
Old 10-22-2010, 09:23 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #11 (permalink)
gtc gtc is offline
abides.
 
gtc's Avatar
 
Join Date: Nov 2006
Location: Seattle, WA
Posts: 8,415
Garage
Is your clutch cable support bracket ok?

link
I thought you were supposed to have the cable connected and under tension before you set the clearance.
__________________
Graham
1984 Carrera Targa
Old 10-22-2010, 10:11 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #12 (permalink)
Registered
 
Join Date: Oct 2009
Location: Sonoma, CA
Posts: 576
Garage
Thanks for all the replies!

Walt, if left in position B, with the screw backed out, the head of the screw won’t clear the heat exchanger. But if I don’t install the screw, the small arm should fit closely to the big arm. I’ll try removing the screw in order to test the clutch. Good suggestion about marking the arm once things get set up correctly. And yes, the bushing at the end of the cable arm is good.

Msterling: The whole story is spelled out in the thread I linked to in the first post of this thread. The short story is that the clutch worked fine pretty much right up until the pedal hit the floor. However, there was a sound a bit like a softly squeaking belt (clutch was engaged), though it came and went and very well may have actually been a squeaky belt. The pedal started feeling like it had less resistance maybe a mile or two before it went to the floor. But prior to that it was business as usual. I never had to adust the clutch because of a cracked and stretching release fork or cable. In that thread, some folks suggested a broken release fork or a throw-out bearing that got pulled out.

GTC: The support bracket is solid. And according to the article on this site and the 101 Projects book, the initial clearance setting is to be done with the cable disconnected. Once you get the 1.2mm measurement, you connect the cable and set the gap to 1.0 mm.
__________________
1983 SC
Blog
Old 10-22-2010, 11:09 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #13 (permalink)
Registered
 
Walt Fricke's Avatar
 
Join Date: May 2004
Location: Boulder, Colorado
Posts: 7,275
Right - if you wanted, you could us a shorter or longer bolt from your junk box. Common M8x1.25 thread. Though of course you should not have to do so.

Looking more and more like something inside the bell housing. Alas.

Some day the fiber optic viewers will get way down in price. Maybe not like digital VOMs, but close. Then we'll all be able to look into some places we can't easily do now. The holes in the top area of the tranny bell housing actually allow a view of the top of the TOB/clutch fork, but it is very hard to look into this with the tranny in the car. You can remove the starter to get a view, but that, too, is a hard view to get in the car, I think. Haven't tried that one.
Old 10-22-2010, 11:33 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #14 (permalink)
Registered
 
Join Date: Oct 2009
Location: Sonoma, CA
Posts: 576
Garage
I ran home at lunch and crawled under the car. I'm even more confused now. Or less confused. I don't know. So I hooked up the cable and things back there started to appear to fall into place. Here's a pic of the setup with the short arm set on the spline so the gap to the adjuster is larger.

With this setup, the clutch pedal is positioned about halfway to the floor in relation to the position of the brake pedal.



And here's a pic of the setup with the short arm set on the spline so the gap to the adjuster is smaller.

With this setup, the clutch pedal is closer to the floor---almost all the way down.




With both settings, I got some resistance at the pedal, like you'd get with a functioning clutch. But I can't tell if the clutch is working or if something inside is just stretching, as there's not enough pedal travel. (Though with the first setup, it felt good.) I admit I don't have a clear picture in my head of how the system works. Lots of threads describe a situation like mine as a broken clutch fork, as many have suggested.

By the way, does the helper/omega spring look to be in the correct position here? Looks more curled under/farther from the heat exchange than most pics I've seen.

__________________
1983 SC
Blog
Old 10-22-2010, 01:40 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #15 (permalink)
Reply


 


All times are GMT -8. The time now is 09:36 PM.


 
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2025, vBulletin Solutions, Inc.
Search Engine Optimization by vBSEO 3.6.0
Copyright 2025 Pelican Parts, LLC - Posts may be archived for display on the Pelican Parts Website -    DMCA Registered Agent Contact Page
 

DTO Garage Plus vBulletin Plugins by Drive Thru Online, Inc.