Strange clutch problem (Page 1/1)
sd_iconoclast DEC 11, 08:36 PM
I have an 88 formula with a Getrag 5 Speed.
A few months ago, I started feeling a strange vibration through the clutch pedal.
Then one day the clutch pedal did not return, and the clutch was left stuck in a state where the transmission is permanently coupled to the engine.
Further inspection shows that the master and slave cylinder seem to be working just fine. No leaks, and I cannot force the slave pushrod back into the slave cylinder.
But, there is about a 1/2" gap between the end of the slave pushrod and the arm on the transmission that depresses the clutch pressure plate.
I have tried to move this arm by hand but it is stuck in the depressed position. It will not move at all.
In other words, the clutch slave piston (I have Rodney's improved slave) is fully extended but the pushrod is still about half an inch from the actuator arm on the clutch.
Has anyone seen this before?
Any theories as to what has happened?
Neils88 DEC 11, 09:19 PM
It sounds like either a failed clutch pressure plate or a seized linkage. If you've checked that nothing is bent externally, you'll likely have to pull the transmission to do a detailed inspection. If you have a boroscope, you can open the inspection plate at the bottom of the transmission and see if you can see the problem.

If it is internal, there really isn't much you can do without pulling the transmission though. Perhaps lubricating the linkage and seeing if you can jiggle it loose. I wouldn't hold my breath on that though.
RotrexFiero DEC 11, 10:20 PM
It may be the clutch throw out bearing. If the bearing was failing that would explain the weird feel and noise. And, then the eventual failure of the bearing, it probably locked the clutch up.

Yes, you will have to pull the transmission to change this.

One of the reasons I never sit in traffic with my clutch engaged for long periods of time. It creates excessive wearing. I learn this a while back.

A very inexpensive part but while you are there you should just replace your clutch.
Patrick DEC 12, 12:10 AM

quote
Originally posted by RotrexFiero:

One of the reasons I never sit in traffic with my clutch engaged for long periods of time. It creates excessive wearing.



I think you mean disengaged. Pressing the clutch pedal towards the floor disengages the clutch (by pushing the release bearing against the pressure plate release fingers).


quote
Originally posted by sd_iconoclast:

I have an 88 formula with a Getrag 5 Speed. A few months ago, I started feeling a strange vibration through the clutch pedal.



Hopefully, this isn't what your problem turns out to be, but it sounds awfully similar. - Getrag Input Shaft Sleeve/Bearing Assy Supplier?


quote
Originally posted by Bloozberry:

I'm repairing a customer's car that had a vibration in the clutch pedal when engaging or disengaging the clutch. Now that it's apart, it's clear what the problem was... the sleeve that the throw-out bearing slides on (that's normally an integral part of the input shaft bearing) is separated from the bearing.


[This message has been edited by Patrick (edited 12-12-2021).]

sd_iconoclast DEC 12, 03:00 AM
I was hoping to hear that there is an easy fix for this. Bummer.
I have to admit that the input shaft bearing theory sounds like a good one.
Well, at least Rodney has replacement now.

I guess I have no choice but to pull the cradle.
I have done it once before on this car and it was no fun.
I used a step by step writeup from this forum of how to pull the cradle. Now I cant find it again.
Does anyone know where it is?
Patrick DEC 12, 05:07 AM

quote
Originally posted by sd_iconoclast:

I used a step by step writeup from this forum of how to pull the cradle. Now I cant find it again. Does anyone know where it is?



Did you look in FAQs & HowTos ?
fierofool DEC 12, 08:18 AM
sd_iconoclast, one of our members had a similar issue several months ago. His problem was that one side of the clutch release fork broke off.
eti engineer DEC 12, 05:08 PM

quote
Originally posted by sd_iconoclast:

I have an 88 formula with a Getrag 5 Speed.
A few months ago, I started feeling a strange vibration through the clutch pedal.
Then one day the clutch pedal did not return, and the clutch was left stuck in a state where the transmission is permanently coupled to the engine.
Further inspection shows that the master and slave cylinder seem to be working just fine. No leaks, and I cannot force the slave pushrod back into the slave cylinder.
But, there is about a 1/2" gap between the end of the slave pushrod and the arm on the transmission that depresses the clutch pressure plate.
I have tried to move this arm by hand but it is stuck in the depressed position. It will not move at all.
In other words, the clutch slave piston (I have Rodney's improved slave) is fully extended but the pushrod is still about half an inch from the actuator arm on the clutch.
Has anyone seen this before?
Any theories as to what has happened?



PM me. I have made a pdf of the doc for which you are looking...