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-   -   Clicking noise felt in clutch pedal (https://www.ft86club.com/forums/showthread.php?t=154282)

RToyo86 12-11-2023 08:30 AM

Clicking noise felt in clutch pedal
 
Just noticed this after drive into work this morning. Clutch done 1200km ago. Exedy OEM flywheel and clutch, new front bearing cover and battle garage TOB, verus fork+pivot.

Pedal is making a tick sound about 1-2inch off the floor which can be felt in the pedal. Edit only when pressing the pedal to the floor.

I also have a Forester slave cylinder installed for added information.

Any ideas as to what's happening?

Clutch Pedal is currently adjusted to same height as brake pedal. Releasing pedal from the floor, the clutch starts to grab at the end when pedal is almost fully released.



https://youtu.be/Zg74JELz0jA?si=UU_zgIs_Q31MdMvR

x808drifter 12-11-2023 09:03 AM

Just to confirm. It's only clicking as it goes to the floor but not at all when it comes back up right?

RToyo86 12-11-2023 09:14 AM

Quote:

Originally Posted by x808drifter (Post 3598236)
Just to confirm. It's only clicking as it goes to the floor but not at all when it comes back up right?

Yes, just clicks as press to the floor, no noise when I release pedal.

blsfrs 12-11-2023 09:43 AM

First, I'd try adjusting the clutch rod so that it engages earlier. You could also remove the assist spring.

Ultramaroon 12-11-2023 04:22 PM

Can you squeeze the fluid out of the slave cylinder by pulling the top of the fork forward? Do that before touching anything else.

RToyo86 12-11-2023 06:03 PM

Quote:

Originally Posted by Ultramaroon (Post 3598276)
Can you squeeze the fluid out of the slave cylinder by pulling the top of the fork forward? Do that before touching anything else.

Yes it's very quishy. And the rod has play.

To follow up, noise was gone when car was cold and returned after I drove it 35km home. Maybe air in the system?

https://youtu.be/vKVNMSVC1b0?si=A5GXMie1kCXfuT6O

Ultramaroon 12-11-2023 11:36 PM

Quote:

Originally Posted by RToyo86 (Post 3598285)
Yes it's very quishy. And the rod has play.

Not returning is ok. We're squeezing the fluid back into the reservoir the same way that clutch wear does. This test confirms that the clutch pedal linkage allows the supply port to open in the released position. The only thing pulling fluid back out of the reservoir is a dinky little spring in the slave cylinder. It will eventually take up the slack. Alternatively, the clutch pedal can be pressed a couple times. If the fluid is really squeezed out, the helper spring may hold the pedal to the floor the first time it's pressed. No biggie.

It's not air because that would have the opposite effect. Clutch would not disengage. My money's on the pressure plate. :(

EndlessAzure 12-12-2023 02:28 AM

Quote:

Originally Posted by RToyo86 (Post 3598285)
Yes it's very quishy. And the rod has play.

To follow up, noise was gone when car was cold and returned after I drove it 35km home. Maybe air in the system?

https://youtu.be/vKVNMSVC1b0?si=A5GXMie1kCXfuT6O

Cylinder rod movement looks normal to me

RToyo86 12-12-2023 07:26 AM

Quote:

Originally Posted by Ultramaroon (Post 3598311)
Not returning is ok. We're squeezing the fluid back into the reservoir the same way that clutch wear does. This test confirms that the clutch pedal linkage allows the supply port to open in the released position. The only thing pulling fluid back out of the reservoir is a dinky little spring in the slave cylinder. It will eventually take up the slack. Alternatively, the clutch pedal can be pressed a couple times. If the fluid is really squeezed out, the helper spring may hold the pedal to the floor the first time it's pressed. No biggie.

It's not air because that would have the opposite effect. Clutch would not disengage. My money's on the pressure plate. :(

I was afraid of it requiring another transmission drop. Anything to look for when inspecting things?
Out of curiosity what could cause pressure plate noise only when system is hot? I noticed it doesn't make the sound wheb everything is cold after it sits for several hours.


Follow up question to that, am I okay to clean up then swap my OEM pressure plate to see if it fixes the problem?



Edit drove to work this morning.
No noise for first 15 minutes driving. Got caught in bumper to bumper on highway for 10 minutes. Noises started again.
Then it went away for the few shifts needed to get up to highway speeds. After I got off the highway noise returned for the next set of shifts to get to work.

RToyo86 12-12-2023 06:54 PM

Update.

Decided to fiddle around with clutch pedal height to see if I could make sense of this and I think I may have made some progress.

Previously had the cruise control switch adjusted to the same height as the brake pedal and then brought the clutch pedal height to get is as close as possible to remove slop

I made 3 adjustments on the drive home since it happens once it warms up. Ended up shortening it a few spins, enough that the pedal still sits at the same height but has some slop before anything happens on initial press.

Final adjustment was done in the driveway and took a spin around the block.

Ultramaroon 12-13-2023 12:29 AM

I've been thinking that I should explain my reasoning. I'm not focused as much on the click as I am on the change in engagement point. It's not ok for the clutch to "start to grab" so late in the pedal arc. Was this gradual? How did it behave when you first installed it?

Depending on the condition of the pressure plate, it might not be crazy to consider reusing it. It should show little to no wear, nor any hot spots. I've seen both gently used, and completely neglected.

You have the Verus fork. I can only explain the click with a worn stock fork. This is a mystery.

RToyo86 12-13-2023 07:36 AM

Quote:

Originally Posted by Ultramaroon (Post 3598374)
I've been thinking that I should explain my reasoning. I'm not focused as much on the click as I am on the change in engagement point. It's not ok for the clutch to "start to grab" so late in the pedal arc. Was this gradual? How did it behave when you first installed it?

Depending on the condition of the pressure plate, it might not be crazy to consider reusing it. It should show little to no wear, nor any hot spots. I've seen both gently used, and completely neglected.

You have the Verus fork. I can only explain the click with a worn stock fork. This is a mystery.

I think your initial diagnosis makes sense given info I provided. First drive after install felt like clutch grabbed at end of the pedal. With my old TOB so close to failure it sort of operated like a button on/off switch.

Now it feels properly gradual which might be part of the change in feel with the BG TOB?.
I also swapped back to OEM slave just to get a baseline when I adjusted the pedal. Going to keep an eye on the sound but the way it's adjusted currently it grabs more naturally.
In having adjusted it so much I may have adjusted it last time a bit too long?

I am planning to keep an eye on it and gradually start pushing the clutch more and more just to see if there's any slip during harder shifts.

Edit turned off traction control and did a few quicker shifts from 2-3. Also got rear end loose in first leaving a stop while making a turn. Pressure plate looks to be supplying enough pressure. Noise still happens at a stop when I press in pedal on occasion. Doesn't happen every time.

Ultramaroon 12-13-2023 02:17 PM

Quote:

Originally Posted by blsfrs (Post 3598240)
First, I'd try adjusting the clutch rod so that it engages earlier. You could also remove the assist spring.

^^^ credit ^^^ I prefer leaving the spring installed and going with the Forester slave. Gotta plug my signature mod even though I let it get out of control with the stainless braided line. That was silly. :(

RToyo86 12-13-2023 07:49 PM

Quote:

Originally Posted by Ultramaroon (Post 3598447)
^^^ credit ^^^ I prefer leaving the spring installed and going with the Forester slave. Gotta plug my signature mod even though I let it get out of control with the stainless braided line. That was silly. :(

Good chance I'll be swapping that slave back in. Even with the Mtec assist spring the pedal is still so very very light.

Definitely a good mod and cheap!


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