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-   -   Upgraded Clutch now seems like TOB is pressing on pressure plate when not depressed. (https://www.ft86club.com/forums/showthread.php?t=102500)

Rybot 03-05-2016 11:17 PM

Upgraded Clutch now seems like TOB is pressing on pressure plate when not depressed.
 
Hey guys.

Just got done with my first clutch install and now I've got a small problem.

I followed the DIY for clutch replacement so I'm very much hoping everything was done properly, but that does not seem to be the case.

Once finished, on startup, car would lurch and not come out of gear or change while running. I can drive it once it's going, but I have to rev match to get the gears to an extent. The clutch might be 30% operable in terms of release.

I looked at the clutch slave and it seems like it's extended to a point where the TOB is now by default, pressing against the pressure plate.

How far should the slave shaft extend when the clutch is not depressed?

I tried a very quick bleed from the slave since I don't have any fluid with me to see if that would help. It didn't.

Anyone have a suggestion? I REALLY don't want to take the transmission out again. Spent 12 hours today doing it by myself and am not looking forward to it again if I need to.

Anything?

Edit: Would the TOB have fallen off the input shaft and not able to step back onto the higher diameter shaft that it should rest on?

Ultramaroon 03-05-2016 11:43 PM

Assuming you did not adjust the clutch pedal throw, the issue would be either air in the system, or something went wrong under the bell housing during assembly.

Rybot 03-05-2016 11:51 PM

Quote:

Originally Posted by Ultramaroon (Post 2570593)
Assuming you did not adjust the clutch pedal throw, the issue would be either air in the system, or something went wrong under the bell housing during assembly.

I really wish I had a bleed kit, but what I did was essentially cracking the bleed nozzle and pull the fork forward to push the slave shaft back into itself to bleed some fluid. I retightened during the fork pull so I wouldn't introduce and air into the system.

How could air have gotten into the system to begin with? I only took off the bolts holding the slave on which I thought didn't introduce and air into the system, right?

What could have gone wrong in the bell housing?

Spartarus 03-06-2016 12:01 AM

Did

You

Adjust

The

Pedal

Position

?

Rybot 03-06-2016 12:04 AM

Quote:

Originally Posted by Spartarus (Post 2570606)
Did

You

Adjust

The

Pedal

Position

?

No.

I even went under the pedals and gave the startup sensor thing under the clutch pedal plenty of breathing room in case that was stopping the pedal from returning further. It wasn't.

Spartarus 03-06-2016 12:20 AM

1 Attachment(s)
Quote:

Originally Posted by Rybot (Post 2570613)
No.

I even went under the pedals and gave the startup sensor thing under the clutch pedal plenty of breathing room in case that was stopping the pedal from returning further. It wasn't.

Good to know. Btw, The TOB should rest gently on the pressure plate.

Did you replace the TOB? If so, did you make sure the fork was correctly seated on the pivot?

The slave cyl should stick out this far.

Spartarus 03-06-2016 12:27 AM

If it all looks fine relative to the picture, I suspect air. If it is, you will need to bleed it properly. Fingers will not generate sufficient pressure, nor will they provide motive flow to drive any air out.

You can do it solo, just ensure any bleeding line is submerged in fluid.

Ultramaroon 03-06-2016 12:50 AM

Quote:

Originally Posted by Rybot (Post 2570596)
I really wish I had a bleed kit, but what I did was essentially cracking the bleed nozzle and pull the fork forward to push the slave shaft back into itself to bleed some fluid. I retightened during the fork pull so I wouldn't introduce and air into the system.

How could air have gotten into the system to begin with? I only took off the bolts holding the slave on which I thought didn't introduce and air into the system, right?

What could have gone wrong in the bell housing?

Bleed kit isn't necessary. I use the same technique. As long as the piston didn't fall out of the slave, you are correct. No air.

If the fork freely retracts as you've proven by the bleed technique and the clutch "mostly" disengages, try adding some more throw to the pedal.

Did you ever lower the pedal from stock? Something smells fishy.

Rybot 03-06-2016 01:22 AM

Quote:

Originally Posted by Spartarus (Post 2570628)
Good to know. Btw, The TOB should rest gently on the pressure plate.

Did you replace the TOB? If so, did you make sure the fork was correctly seated on the pivot?

The slave cyl should stick out this far.

I did replace the TOB, but I assumed the fork was seated properly. The clips were installed properly as well and I tested the fork itself with TOB installed to make sure the movement was smooth.

My slave sticks out that far, so I guess I'm good on that front.

I feel like the TOB is somehow stuck on the spline park of the input shaft.

Though at full depression of the clutch pedal, the TOB isn't doing its job. Damn.

Rybot 03-06-2016 01:25 AM

Quote:

Originally Posted by Spartarus (Post 2570632)
If it all looks fine relative to the picture, I suspect air. If it is, you will need to bleed it properly. Fingers will not generate sufficient pressure, nor will they provide motive flow to drive any air out.

You can do it solo, just ensure any bleeding line is submerged in fluid.

Yeah, my slave shaft comes out about that far, but at full depression it's not disengaging the clutch disk.

I can try bleeding it tomorrow or something, but I don't think there's air in the system.

Rybot 03-06-2016 01:28 AM

Quote:

Originally Posted by Ultramaroon (Post 2570652)
Bleed kit isn't necessary. I use the same technique. As long as the piston didn't fall out of the slave, you are correct. No air.

If the fork freely retracts as you've proven by the bleed technique and the clutch "mostly" disengages, try adding some more throw to the pedal.

Did you ever lower the pedal from stock? Something smells fishy.

I did lower the pedal from stock, but after I bled the slave I loosened the under pedal clutch sensor to get the pedal plenty of room to move up if it was under stress.

There was no further movement of the pedal upwards, unfortunately. Would I need to pump it a few times after I loosen the sensor to try and get it to spring back upwards?

Rybot 03-06-2016 01:34 AM

Uhhhh, @Spartarus. You might be right.

I feel like an idiot. I left the car already tonight since I've been at it for so long, but upon remembering how to adjust the footwell clutch pedal actuator I might just need to adjust the fucking pedal.

That doesn't answer the question of why the TOB won't release the clutch disk at full depression, though, unless that's part of the same problem.

Spartarus 03-06-2016 01:45 AM

If you lowered the pedal from stock you will need to raise it again. Any aftermarket clutch will have a different engagement point.

Ultramaroon 03-06-2016 01:52 AM

Quote:

Originally Posted by Rybot (Post 2570663)
I did lower the pedal from stock, but after I bled the slave I loosened the under pedal clutch sensor to get the pedal plenty of room to move up if it was under stress.

There was no further movement of the pedal upwards, unfortunately. Would I need to pump it a few times after I loosen the sensor to try and get it to spring back upwards?

What Spartarus said. All clutches are different, even the same models from one unit to the next. The pedal throw directly affects the travel of the slave plunger.

It SHOULD NOT come up any further just because the switch is backed out. The master plunger must always be allowed to fully extend. It is critical to maintain the self-adjusting function of the hydraulic system.


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