Seeking advice on sticking clutch pedal.

After not much use the last 24 years, my clutch pedal started to sporadically stick on the return about an inch short of full travel. I checked that the pedal return spring was attached and also lubricated the pivot point. I exercised it a number of times and got it to the point where I couldn't get it to stick if I tried. I then went for a test drive and it stuck after the first depression! The clutch operation is fine but it is hard enough to double clutch those tiny pedals with size 13 shoes, and not knowing where the pedal is does not help.

I checked the operation of the pivot point and did not detect much in the way of resistance or binding. Is there any history of pedal return springs getting weak? I thought I would ask first because it looks like a pain to replace the spring.


Thanks,

Don
 
Don, I've found the plastic (nylon?) pivot bushing to be problematic on all of mine. Look closely to see if the entire bushing is moving (pivoting) with the clutch pedal, or if just the pedal is moving but not the bushing. It is designed so the bushing itself should not move, only the pedal within it. But the bushing sticks to the pedal's pivot and the small retaining tab that should prevent the bushing from moving gets stripped, allowing it to move instead of the pedal. This causes strange sticking of the pedal. The plastic bushing actually rusts to the clutch pedal's metal pivot (no idea how that happens). Unfortunately it is a bit of a bitch to remove and ream out or replace the bushing, and polish the pedal pivot. I tried adding a zerk fitting to allow periodical lubrication but there is no way to mount it without interfering with things. Also check the brake side for the same problem, although it is a slightly different design on that side (less contact surface area between the parts) and seems less problematic.
 
Don, I've found the plastic (nylon?) pivot bushing to be problematic on all of mine. Look closely to see if the entire bushing is moving (pivoting) with the clutch pedal, or if just the pedal is moving but not the bushing. It is designed so the bushing itself should not move, only the pedal within it. But the bushing sticks to the pedal's pivot and the small retaining tab that should prevent the bushing from moving gets stripped, allowing it to move instead of the pedal. This causes strange sticking of the pedal. The plastic bushing actually rusts to the clutch pedal's metal pivot (no idea how that happens). Unfortunately it is a bit of a bitch to remove and ream out or replace the bushing, and polish the pedal pivot. I tried adding a zerk fitting to allow periodical lubrication but there is no way to mount it without interfering with things. Also check the brake side for the same problem, although it is a slightly different design on that side (less contact surface area between the parts) and seems less problematic.
When I was looking for places to lubricate up there, I was moving the pedal up and down and did not notice the plastic moving. Since it is intermittent, I should take another look. If there is rust inside, there is a good chance that the lubricant may have worked it's way inside the plastic tube by now and hopefully loosen things up.

What has your experience been with the spring? I noticed it was pretty easy to press the pedal with my hand so I'm wondering if it is weak.
 
Last edited:
What has your experience been with the spring?
If you are referring to the standard type "supplement" pull spring that attaches to the front of the pedal arm, none of my X's had them when I got them (and still don't). If you are referring to the circular torsion spring that goes around the pivot, they all feel pretty much the same on mine and I don't recall anyone ever saying it has gone bad. So I doubt it is a spring issue.
 
Don, I've found the plastic (nylon?) pivot bushing to be problematic on all of mine. Look closely to see if the entire bushing is moving (pivoting) with the clutch pedal, or if just the pedal is moving but not the bushing. It is designed so the bushing itself should not move, only the pedal within it. But the bushing sticks to the pedal's pivot and the small retaining tab that should prevent the bushing from moving gets stripped, allowing it to move instead of the pedal. This causes strange sticking of the pedal. The plastic bushing actually rusts to the clutch pedal's metal pivot (no idea how that happens). Unfortunately it is a bit of a bitch to remove and ream out or replace the bushing, and polish the pedal pivot. I tried adding a zerk fitting to allow periodical lubrication but there is no way to mount it without interfering with things. Also check the brake side for the same problem, although it is a slightly different design on that side (less contact surface area between the parts) and seems less problematic.
I checked today and the plastic is not moving. The brake side works fine. Regarding springs, I was referring to the supplemental one because I forgot there was the circular one. I checked today by feel, and it appears mine is inside a rubber boot. I shot some WD40 up in there to see if it helps. It feels like the problem may be getting better with use. I've got about 45 miles on the car (without going more than 7 miles from my house) and other things are starting to feel a bit more "normal" like the brakes and shocks. When I first drove, it seemed like the wheels may have been a bit out of round but I guess running them a bit and getting them hot has made them round again. Got up to about 60 mph and pretty smooth.
 
Just for grins, loosen the nut on the pivot bolt.
I tried the nut loosening idea but no change. I also gave the end of the bolt a whack with a hammer to free things up but no change. I then went the other extreme and got it really tight. No change. Seemed like it should have had some effect but there must be some other forces at play. I think I will have to pull the seat out so I can get a much better look. The last time I was up close was in the mid 80s when I rebuilt the master cylinders, and it wasn't fun then. I'm pretty sure the intervening years are not going to make it much easier if I need to start yanking things out from up there.
 
I too have a clutch which doesn’t return without help. Without hydrolic oil all seperate parts work smooth and freely. Filled with fluid the pedal works heavy and does not return by itself. I had to make a new break line nipple under the dash. I now think that I bent the line a bit to far out causing a dent which limits the oil to move freely between the master and slave. What’s your opinion?
 
I would think that if it is just a line restriction it would just take longer - kind of like a bad brake hose. My hydraulics seem to be OK but there seems to be some intermittent binding about the last inch or so.
 
I would think that if it is just a line restriction it would just take longer - kind of like a bad brake hose. My hydraulics seem to be OK but there seems to be some intermittent binding about the last inch or so.
I thought of that too. But a restriction might also cause less return pressure. Not enough anymore to start the pedal up movement.
 
Unless the dent/kink in the line is severe I don't think it will affect the pedal return. If it did, then it would also slow the inward movement of the pedal the same way. So you will notice more problems than just a sticky pedal return.

However another thought occured to me. Depending on the year of X, some have a spring on the slave cylinder that pulls the plunger back into the slave, while others are the opposite with a spring that pulls the plunger toward the clutch. If you have the first type (pulls it into the slave) make sure that spring is still attached and working. If you have the second type (pulls it away from the slave) consider changing it to work like the other style. There is a old thread that goes into detail on this:
https://www.tapatalk.com/groups/xweb/clutch-pedal-spring-to-use-or-not-to-use-t8988.html

I'm not sure how much this can affect the pedal return (honestly not likely a lot), but might be worth a look.
 
I've got the spring pulling toward the slave. I've heard later models do it the other way, which I have seen on no other car. That technique must have been invented by a throw out bearing manufacturer. I think my pedal sticking may be right at the end of the hydraulics moving. I think I will pull the seat and get my head way up in there and see what is going on. Or, I could just keep driving it, as it seems that it is getting a bit less frequent with use. So far, I've had it out 5 times, got about 45 miles on it without getting further than 7 miles from my house.
 
My problem wasn’t solved by fixing the dent in the clutch line. Come to think of it, if it were the hydrolics the pedal should have moved freely once depressed, right? That was not the case. If i pull the pedal, the slave is reacting instantly. I guess there is something with the pedalbox then. The pedal feels heavy and sticks when pressure is applied from the clutch. Hmmm?
 
Maybe try adjusting the push rod on the slave to the point the slave no longer moves the clutch (i.e. enough free play, if that is possible). Then see how the pedal feels/moves without the resistance of the clutch against it. That should pretty much isolate it to the pedal.

As I said earlier, I've found the pivot bushing to be very problematic, and I suspect it is the cause of these issues. I also suspect the use a secondary return spring on the clutch pedal (the external one that attaches to the arm of the pedal, facing the driver) was added as a after thought to help overcome the inherent problems with this bushing. Just my opinion, no offense to all of our beloved Fiat devotees. But when the bushing is working smoothly and freely, that extra spring seems to not be needed.

Look at Bernice's thread about a replacement design of bushing for information:
https://xwebforums.com/forum/index.php?threads/that-plastic-pedal-box-bearing.25400/#navigation
 
Thank you. Just read it after I solved the problem by myself. But it is spot on. When I assembled the box I didn’t notice the small gap in the plastic bushing. This bushing was a bit out of line causing some friction between pedal and cylinder. Solved.
 
When I assembled the box I didn’t notice the small gap in the plastic bushing.
The design is suttle in how it goes together and could easily be missed. It's also not extremely robust. Mine was already damaged/worn so the bushing was no longer located with the little flat slot and thin metal key (the key had cut the slot all the way around the plastic), allowing it to rotate. I also noticed it tends to wear more (internal bore) on one end, due to how the two pedals interact with it. Replacing the bushing with a new one would have been best, but I did not want to wait for one to be shipped (they can be a little difficult to find at times). So I decided to slightly modify it. I reversed its orientation (to swap the worn bore to the other end) and made a new larger flat pad (rather than slot) on it for a new design key. Then I added a larger piece of square stock welded on as the new key (so it can't move like the stock key did), in addition to the existing thin key (keeping it from moving axially). The bushing will never rotate with this change.
 
Maybe try adjusting the push rod on the slave to the point the slave no longer moves the clutch (i.e. enough free play, if that is possible). Then see how the pedal feels/moves without the resistance of the clutch against it. That should pretty much isolate it to the pedal.

As I said earlier, I've found the pivot bushing to be very problematic, and I suspect it is the cause of these issues. I also suspect the use a secondary return spring on the clutch pedal (the external one that attaches to the arm of the pedal, facing the driver) was added as a after thought to help overcome the inherent problems with this bushing. Just my opinion, no offense to all of our beloved Fiat devotees. But when the bushing is working smoothly and freely, that extra spring seems to not be needed.

Look at Bernice's thread about a replacement design of bushing for information:
https://xwebforums.com/forum/index.php?threads/that-plastic-pedal-box-bearing.25400/#navigation
I had checked out Bernice's article earlier. The photos were very helpful, as I have not been able to find any useful drawings or photos in any of the manuals I have. My view is a bit obstructed but I'm hoping I'll get a better view with the seat out. One of the few things I remember about doing the master cylinders was pulling out the steering column. I hope it doesn't need to go that far.
 
You should be able to see things well enough without removing the steering column. I was able to remove the entire pedal box with it in place (but it was harder to do).
 
You generally don’t have to remove the column from the car, just dropping it down will give you the the space you need. I am a bit smaller so perhaps I don’t need the space others do.
 
Back
Top