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Clutch Problem

So my 87 930 has an intermittent clutch issue. At times the clutch feels great; pedal is consistent and engages/disengages correctly. But more often than not, the clutch pedal is very hard and feels like there are two stages. The pedal will even stick down requiring me to press it a second time to unstick and engage.

I've read all the threads regarding clutch problems, and it appears my issue can be anything from pedal cluster, cable, omega spring, or throw-out bearing. I've doused the omega spring and clutch linkage with PB blaster with no change.

Does anyone have an educated guess or recommendation on what to tackle first?
Old 04-11-2010, 04:12 PM
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How free is the clutch cable? Might try disconnecting it from the control arm the tranny and see how easily it move without tension on it. From there, you may want to pull the floorboards up and check the lubrication of the cluster. Rule those two out anyway.

TOB might be bound up on the guide tube.
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Old 04-11-2010, 05:33 PM
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good call, I'll start with checking the cable. That omega spring scares me a bit
Old 04-11-2010, 05:56 PM
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I don't think omega springs can hang-up unless their mounting/pivot points are totally welded with corrosion. They either work....or they break.
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Old 04-11-2010, 06:03 PM
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Originally Posted by mark houghton View Post
I don't think omega springs can hang-up unless their mounting/pivot points are totally welded with corrosion. They either work....or they break.
OK, I wasn't sure if they start to deteriorate. I watched the cable and spring from underneath while a friend worked the clutch. I didn't see anything obvious, except about half way down there was a hesitation in movement, then everything moved easily again.
Old 04-12-2010, 02:45 AM
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Yep mine does the same thing but the pedel doesn't stick down. It feels as if it going to stick but will pop up right at the engagement point ( better be on the gas or risk a idiot moment at a light ). Sometimes it is perfect and others it feels as if you are trying to push your foot through concrete. We rebuilt the cluster with the bronze bushings and replaced the cable with results no better than before. It started after replacing the clutch and pressure plate. The first clutch replacement wouldn't even dis engage enough to get the car in gear so out comes the motor again and replaced with a new unit. Now I can drive the car but at the expense of tricky clutch action. It is a Kennedy light weight pressure plate and clutch, new throw out bearing with the extended sleeve .Since all the headache's when I finally break down and drop the motor again I will replace it with a Patrick motorsport's unit. I just try to stay out of the city with it now to keep from too many stop and start's.
Old 04-12-2010, 07:34 AM
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Quote:
Originally Posted by LOWFAT View Post
Yep mine does the same thing but the pedel doesn't stick down. It feels as if it going to stick but will pop up right at the engagement point ( better be on the gas or risk a idiot moment at a light ). Sometimes it is perfect and others it feels as if you are trying to push your foot through concrete. We rebuilt the cluster with the bronze bushings and replaced the cable with results no better than before. It started after replacing the clutch and pressure plate. The first clutch replacement wouldn't even dis engage enough to get the car in gear so out comes the motor again and replaced with a new unit. Now I can drive the car but at the expense of tricky clutch action. It is a Kennedy light weight pressure plate and clutch, new throw out bearing with the extended sleeve .Since all the headache's when I finally break down and drop the motor again I will replace it with a Patrick motorsport's unit. I just try to stay out of the city with it now to keep from too many stop and start's.
Hmmm....my Kennedy PP works smooth as silk. Something somewhere binding up.
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Old 04-12-2010, 09:41 AM
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I will bet you dollars to donuts it is the guide tube. The throwout bearing is hanging on the guide tube.

I just removed my engine and trans to find out why I was having the same symptoms. My guide tube is grooved from throwout bearing wear.

I had the same symptoms:
- easy clutch to a point, then harder to depress with intermittent delayed or sticking return. In my case the symptoms were not there when the car was cold, but got worse as the engine warmed up. I assume heat was making the clearances close a bit.
- I suspect last clutch job the PO either did not change out the $28 guide tube or did not lubricate it.

Anyway, this is my theory for my problem with the same symptoms as yours. It could be this is your issue as well.

A few points. I did notice if your clutch is out of adjustment, you can depress the pedal to the point the spring under the floorbaord will actually work against you and will try to pull your pedal to the floor. So be sure your clutch cable and pedal are adjusted correctly. I think it is 25mm total cable movement measured at the clutch cable lever.

Good luck
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Old 04-12-2010, 09:45 AM
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Do you guys lube up the TOB when installing new clutches? I've had no problem with my KEP, stage 2 clutch.
Old 04-12-2010, 09:54 AM
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Always.. and with a grease that has a high percentage of molybdenum disulfide it it.
Most Moly grease has only 4-6% molybdenum disulfide in it and Moly paste usually has 65% in it.
CV joint grease would work well.

Molybdenum disulfide bonds to ferrous metals like steel and cast iron.
After the grease has dried up and gone away the dried moly is still there lubricating to some degree.
Old 04-12-2010, 11:08 AM
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My car did the exact same. New clutch cable, no more problem.
Old 04-12-2010, 02:05 PM
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I also have an 87 I had the same problem just a week ago, My bell housing has a window that allows you to see the clutch and the throw out bearing.I sprayed the throw out bearing guide with white lithium grease worked the pedal a bunch of times , my car went from a near undriveable to like new ....just my 2cents
Old 04-12-2010, 05:34 PM
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Quote:
Originally Posted by speednut View Post
I also have an 87 I had the same problem just a week ago, My bell housing has a window that allows you to see the clutch and the throw out bearing.I sprayed the throw out bearing guide with white lithium grease worked the pedal a bunch of times , my car went from a near undriveable to like new ....just my 2cents
I hope my issue is the same as yours. I just got home from a drive and the clutch is working like a dream right now. Where is this bellhousing window?
Old 04-12-2010, 05:53 PM
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The window on mine is on the drivers side of the bell housing ,you need to be under the car to see it.Between the trans and engine..
Old 04-12-2010, 07:02 PM
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The window on mine is on the drivers side of the bell housing ,you need to be under the car to see it.Between the trans and engine..
cool, thanks. The clutch worked fine again this morning, nice easy smooth pedal. I'll check out that window and spray a little lithium grease in there to lube things up a bit. It seems like that would be the easiest solution, so I'll start there.
Old 04-13-2010, 05:20 AM
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Im going to try the window spray this weekend, I have a feeling he didn't grease anything when it all went back together. I just hate the thought of having to pull the motor again but if I have to I'll bite the bullet. I wonder if there is a way to get some good grease in there through the window without an engine drop.

Last edited by LOWFAT; 04-13-2010 at 03:28 PM..
Old 04-13-2010, 03:26 PM
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Quote:
Originally Posted by s5uewf View Post
I will bet you dollars to donuts it is the guide tube. The throwout bearing is hanging on the guide tube.
Bingo, this is your problem. I bet you have a lightweight clutch with the longer throw-out yoke on it.

My car had the exact problem you described. I changed everything on the outside (pedal box rebuild, cable & omega spring) nothing worked. Had my engine out last year and noticed significant scrubbing on the guide tube the yoke slides over.
I put a good amount of antisieze on the guide before bolting the trans up.

Problem instantly disappeared!

btw: I have the Sachs Sporting clutch (alum clutch and flywheel)
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Old 04-13-2010, 03:50 PM
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With limited access and the TOB barely moving, a lube that flows better will get under the TOB more, but will be more likely to wear off quickly due to heat.
Old 04-13-2010, 03:53 PM
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Here are some pics of my guide tube (sorry crappy pics) but you get the idea.

My guide tube, notice all the chaffing on it.


Stock on the left & Sachs Sporting on the right, thinner clutch means longer throw-out yoke and more area to rub the guide.
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Old 04-13-2010, 03:58 PM
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I've never tried spraying lube on the TO bearing sleave from outside a bellhousing.

I guess it could work or help for a while but I wouldn't use a high temperature high pressure spray grease because if you get any on the clutch disc it will slip forever.
A low temp spray grease like Wurth HHS 2000 or some spray on motorcycle chain lubes for o-ring chains that spray on thin so it will wick into a clearance and then thicken as the solvent quickly evaporates would possibly be best because it will eventually burn off the clutch disc and pressure plate as it slips if you get any on it.
Old 04-13-2010, 04:06 PM
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