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-   -   Notches in clutch travel (https://www.ft86club.com/forums/showthread.php?t=134384)

alex87f 04-29-2019 07:47 AM

Notches in clutch travel
 
Hello guys,

I've noticed that my clutch pedal sometimes has light notches throughout its travel. It doesn't always do it and the clutch pedal may feel perfectly linear one throw, and notchy the next one.

The clutch fluid was just changed, though the car was already doing this before. I think it's become a little more obvious as the fluid change helped make the clutch lighter. TOB was changed 1.5 years / 20k ago as part of a cam plate repair (sic.). Car is a 2013 with 50k on the clock.

I've already had such issues on a previous car, which were caused by the clutch fork bushing having become contaminated with dirt / debris. Removing, cleaning and greasing it had solved the issue permanently. Has anyone attempted such a fix on the twins? And if yes would I be able to do this without bleeding the clutch? Is this a common issue?

Best regards,
Alex

Mr.ac 04-29-2019 09:23 AM

Well that sucks.
And yes some one out there did make a hydraulic replacement unit that does away with the TOB and fork.

Well my only guess is the clutch master cylinder is toast. Not sure if a replacement is worth the time and effort.

BigTuna 04-29-2019 09:27 AM

@celek at Money Shift Racing makes the hydraulic TOB.

http://www.ft86club.com/forums/showt...ighlight=celek

ermax 04-29-2019 10:19 AM

This is a common problem on all cars. If the dirt gets into the grease on the shaft or dries out then it’s going to feel notchy. You can try cleaning the fork externally and then reapply the grease but most likely you will need to drop the tranny and clean up the whole shaft. You will not need to bleed the system to do this job.

Another cause of a notchy feel could be pockets of air in the line cause by a bad master or slave. Is your fluid dark? If so then the rubber seals in the master or slave are going bad.

alex87f 04-29-2019 10:26 AM

1 Attachment(s)
Quote:

Originally Posted by Mr.ac (Post 3212561)
Well that sucks.
And yes some one out there did make a hydraulic replacement unit that does away with the TOB and fork.

Well my only guess is the clutch master cylinder is toast. Not sure if a replacement is worth the time and effort.

How does one kill a master cylinder though? It's always had the proper fluid level, always used DOT4, etc.

The hydraulic TOB sure seems like a nice solution, but buying and installing will be $$$$. I was hoping to just clean the bellhousing bushing the fork rotates on, which would pretty much be a free repair. Basically the articulation point for this part:

VenomRush 04-29-2019 12:15 PM

The notchiness (not sure if thats a word) of the pedal was happening after i adjusted the clutch pedal back to the stockish position. I adjusted it back to a low engagement point (clutch pedal about 2-5mm above the brake pedal) and havn't had the notchy crunchy feel in the pedal ever since. Definitely not a fix.

humfrz 04-29-2019 01:30 PM

Quote:

Originally Posted by alex87f (Post 3212552)
Hello guys,

I've noticed that my clutch pedal sometimes has light notches throughout its travel. Best regards,
Alex

Allow me to refer you to our clutch expert @Ultramaroon.


humfrz

ermax 04-29-2019 01:45 PM

Quote:

Originally Posted by alex87f (Post 3212576)
How does one kill a master cylinder though? It's always had the proper fluid level, always used DOT4, etc.





Age. Rubber only lasts so long even if you’ve always used the correct fluid.

Ultramaroon 04-29-2019 01:47 PM

Might be a couple things.
  1. The TOB is self-centering by design. It floats in its housing but there's a tight spring behind it to make it sticky. Sometimes it gets off center and the wobble can be felt when depressing the clutch pedal. This is more obvious when...
  2. The snout/quill/front cover has worn to the point where the TOB begins to bind as it moves. A lip forms on the quill at the end of travel. If the clutch pedal is raised, the TOB is forced past that lip and the bind can be consistently felt with each operation.

Tcoat 04-29-2019 01:52 PM

Quote:

Originally Posted by Ultramaroon (Post 3212653)
Might be a couple things.
  1. The TOB is self-centering by design. It floats in its housing but there's a tight spring behind it to make it sticky. Sometimes it gets off center and the wobble can be felt when depressing the clutch pedal. This is more obvious when...
  2. The snout/quill/front cover has worn to the point where the TOB begins to bind as it moves. A lip forms on the quill at the end of travel. If the clutch pedal is raised, the TOB is forced past that lip and the bind can be consistently felt with each operation.

This was what happened later in my bearing failure. I would expect it to have started squealing before reaching this stage though.

Ultramaroon 04-29-2019 02:13 PM

Quote:

Originally Posted by Tcoat (Post 3212654)
This was what happened later in my bearing failure. I would expect it to have started squealing before reaching this stage though.

I feel it off and on all the time.

Tcoat 04-29-2019 02:18 PM

Quote:

Originally Posted by Ultramaroon (Post 3212660)
I feel it off and on all the time.

Haven't noticed it in the 60,000 or so miles since it was replaced.

gravitylover 04-29-2019 07:31 PM

Quote:

Originally Posted by Ultramaroon (Post 3212653)
Might be a couple things.
  1. The TOB is self-centering by design. It floats in its housing but there's a tight spring behind it to make it sticky. Sometimes it gets off center and the wobble can be felt when depressing the clutch pedal. This is more obvious when...
  2. The snout/quill/front cover has worn to the point where the TOB begins to bind as it moves. A lip forms on the quill at the end of travel. If the clutch pedal is raised, the TOB is forced past that lip and the bind can be consistently felt with each operation.

The snout could be scored too. Mine was and they didn't replace it when they did the clutch they just cleaned it up with scotch brite and steel wool but it still had ridges on it and they put it back in and hoped for the best. 2 or 3 days after I got the car back I took it in because the clutch was notchy and not releasing completely all the time. downshifts got crunchy too. As soon as I explained what was going on they asked if I had a ride home :( It was a nice walk of ~2 miles. They replaced the snout, and TOB again just for good measure, and all has been well since and that was about 12k miles ago. By trying to save a few dollars on the part the first time they ended up having to drop the tranny again and do it over. I know they changed it because I had them save the old part for me.

FR-Sky 04-29-2019 09:33 PM

I think i have this problem too.
While i the clutch was in traveling motions, it has this little knock or tick sound whatever u call it


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