964 C2 - Clutch Not fully disengaging when warm/hot
#1
Racer
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Hi all
yes it's me again with another question about my recently resurrected C2. Everything is running well except that I have noticed that following a fairly good run, when the car has reached normal operating temperature for at least 20 minutes the gears become difficult to select from a stanstill even with the clutch fully depressed.
The lower the gear ratio, the more noticeable the resistance to engage. It seems that when the car is hot, the clutch is not fully disengaging. (if I sit stationary with the car Idling, fully depress the clutch and try to engage a gear very very slowly it will make a cruching noise that you might expect to hear if someone fluffs a gearchange (not that I'd know that of course!)
Any ideas guys? Is there any adjustment that can be done on the clutch? or is the problem elsewhere?
Thanks for you ideas in advance
Greg
90 C2
yes it's me again with another question about my recently resurrected C2. Everything is running well except that I have noticed that following a fairly good run, when the car has reached normal operating temperature for at least 20 minutes the gears become difficult to select from a stanstill even with the clutch fully depressed.
The lower the gear ratio, the more noticeable the resistance to engage. It seems that when the car is hot, the clutch is not fully disengaging. (if I sit stationary with the car Idling, fully depress the clutch and try to engage a gear very very slowly it will make a cruching noise that you might expect to hear if someone fluffs a gearchange (not that I'd know that of course!)
Any ideas guys? Is there any adjustment that can be done on the clutch? or is the problem elsewhere?
Thanks for you ideas in advance
Greg
90 C2
#2
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sounds like the clutch slave cylinder and old fluid. try bleeding it - nb difficult to get at and its a 2 man job to keep eye on reservoir level and maintain this with topping up.....rarely gets bled in service so dont be surprised to see some heavily contaminated bleed off . if that doesn't work then try replacing.
#3
RL Community Team
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I'm with oldtimer - sounds like you definitely need to bleed the circuit! Usually the slave is dead when your pedal does not return to its highest point. But do the easiest thing first - bleed it, and it will most likely fix your issue.
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#4
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I agree with the above post. Bleed the slave cylinder and replace if necessary...
I would also change the oil in the tranny while you are at it (unless you know it was done recently).
I would also change the oil in the tranny while you are at it (unless you know it was done recently).
#5
Racer
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Thanks guys, with all the same opinions I have a positive feeling that bleeding the system OR replacing the cylinder should sort the problem. I'll have a go and report back.
Greg
Greg
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Greg, Just done the same job for the same reasons. Have a look at the condition of the flexible hose from the cylinder, particularly where the hole sits over the solid pipe. It may be worth changing it while your in there, pedal action is much improved.
Darryl
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#8
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Hi Greg,
I concur on the idea of bleeding the clutch slave cylinder, or even changing it straight away.
After bleeding mine, the problem came back quite soon and eventually both cylinders had to go. It was not too expensive so, in retrospect, I regret not having done the full job first time round.
Take care,
I concur on the idea of bleeding the clutch slave cylinder, or even changing it straight away.
After bleeding mine, the problem came back quite soon and eventually both cylinders had to go. It was not too expensive so, in retrospect, I regret not having done the full job first time round.
Take care,
#9
Racer
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Hi guys
Well, I've done the bleed (well to be truthful, my friend with a garage has done the bleed for me) and the problem has remained. I guess the next step is to change the slave cylinder (as you guys predicted the pedal did not return to its original position once the system was bled).
Does anyone have any guides, instructions or photos on how to change the slave clyinder. Failing that, any tips on the best way to get access and any things to look out for would be much appreciated.
If someone can explain the reason the clutch pedal fails to return to its original position due to a faulty slave cylinder that would help me understand what is going on? Does the slave have some kind of return mechanism, spring etc??
Cheers
Greg
Well, I've done the bleed (well to be truthful, my friend with a garage has done the bleed for me) and the problem has remained. I guess the next step is to change the slave cylinder (as you guys predicted the pedal did not return to its original position once the system was bled).
Does anyone have any guides, instructions or photos on how to change the slave clyinder. Failing that, any tips on the best way to get access and any things to look out for would be much appreciated.
If someone can explain the reason the clutch pedal fails to return to its original position due to a faulty slave cylinder that would help me understand what is going on? Does the slave have some kind of return mechanism, spring etc??
Cheers
Greg
#12
Racer
Thread Starter
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So.... i have a new slave cylinder fitted and the first signs were good. Spent a couple of our using the car without the problems reappearing.
Just when I thought everything was sorted the problem then came back with avengance! Now I even have trouble changing the gears while the car is cold.
So my question is... where to next, should I be considering a change of the master cylinder as well? Is there possibly a problem with my hydraulic lines.
Help needed and as usual, many thanks for your opinions in advance
Cheers
Greg
Just when I thought everything was sorted the problem then came back with avengance! Now I even have trouble changing the gears while the car is cold.
So my question is... where to next, should I be considering a change of the master cylinder as well? Is there possibly a problem with my hydraulic lines.
Help needed and as usual, many thanks for your opinions in advance
Cheers
Greg
#13
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did you change that rubber hose from the slave to the hard line conecting to the master? Mine isnt shot, but it could use replacing. If it was newer more of the fluid from the master would get into the slave, thus pushing the clutch in more. The older rubber loses its stiffness and bulges a lot more than it perhaps should.
I replaced both my master and slave when I went through some issues of changing gears. It helped. I also had a problem with the clutch pedal itself. The wood down there has a stop on it for the clutch pedal. Perhaps it was fine when it was set, but I needed more travel to fully disengage the clutch now. Anyway, I had to adjust it so I got more pedal travel.
Finally I think the pedal assembly itself can fail in a way making the clutch pedal less useful. I think its a pin that just shears off.
I started all this and didn't assume it was my clutch b/c it was all replaced 30,000 miles ago at the car's 60k mile point. I had/have many reasons to believe the PO drove the car like it would break if he pushed it at all. So I felt like the clutch should have plenty of life.
I replaced both my master and slave when I went through some issues of changing gears. It helped. I also had a problem with the clutch pedal itself. The wood down there has a stop on it for the clutch pedal. Perhaps it was fine when it was set, but I needed more travel to fully disengage the clutch now. Anyway, I had to adjust it so I got more pedal travel.
Finally I think the pedal assembly itself can fail in a way making the clutch pedal less useful. I think its a pin that just shears off.
I started all this and didn't assume it was my clutch b/c it was all replaced 30,000 miles ago at the car's 60k mile point. I had/have many reasons to believe the PO drove the car like it would break if he pushed it at all. So I felt like the clutch should have plenty of life.
#14
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#15
Racer
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Thanks Heirsh and Mike_991 for the advice. Thinking about this problem a bit more and the fact that it was exaggerated under hot conditions makes me think that flexible tubing could well be the culprit. A visual inspection didn't reveal any apparent problems but I guess as temperature and pressure increases it is more likely to bulge.
Both cylinders also appear to have a full range of motion when the pedal is pressed. I am fairly confident that the clutch itself is not warn as I had it replaced in 1996 (but only 10k miles ago) and the clutch action is very smooth pulling away etc.
If changing this hose doesn't work, my next move will be the master cylinder.
Does anyone know if the 'kinematic lever update' written up on p-car applies to the 964 as well as the 993?
Cheers
Greg
Both cylinders also appear to have a full range of motion when the pedal is pressed. I am fairly confident that the clutch itself is not warn as I had it replaced in 1996 (but only 10k miles ago) and the clutch action is very smooth pulling away etc.
If changing this hose doesn't work, my next move will be the master cylinder.
Does anyone know if the 'kinematic lever update' written up on p-car applies to the 964 as well as the 993?
Cheers
Greg