Clutch Problems

[martsam]

Hi All,
I changed the travel on the clutch and was able to engage the gears with the engine running. However I cannot sustain the pressure on the clutch as there is a leak at the master cylinder. I changed the internals and thought that would solve the problem but as soon as I pressed the pedal down again I got the leak which causes the loss in hydraulic pressure. The leak is via the pushrod rubber gaiter. What is causing this as the original seal and the new seal were brand new and also a good fit into the master cylinder barrel. Any ideas as to what I can do as I'm getting a bit fed-up of taking out the pedal box to try and fix problem?

Regards

Denis

[Sidecarbod]

Originally Posted by martsam

Hi All,
I changed the travel on the clutch and was able to engage the gears with the engine running. However I cannot sustain the pressure on the clutch as there is a leak at the master cylinder. I changed the internals and thought that would solve the problem but as soon as I pressed the pedal down again I got the leak which causes the loss in hydraulic pressure. The leak is via the pushrod rubber gaiter. What is causing this as the original seal and the new seal were brand new and also a good fit into the master cylinder barrel. Any ideas as to what I can do as I'm getting a bit fed-up of taking out the pedal box to try and fix problem?

Regards

Denis

Sorry to hear that your still having problems. I know that taking the pedal box out is a right pain in the arxe! I don't know what causing your master cylinder to leak but a trick that I learnt is to block off the outlet of the master cylinder (in my case the banjo bolt was tightened down on a large nut with a copper washer either side). This will allow you to apply pressure to the system via the clutch pedal so that you can be 100% sure that you've fixed the problem before you re-fit the pedal box.

Regards,

Pete.

[Purple AK]

Originally Posted by martsam

Hi All,
I changed the travel on the clutch and was able to engage the gears with the engine running. However I cannot sustain the pressure on the clutch as there is a leak at the master cylinder. I changed the internals and thought that would solve the problem but as soon as I pressed the pedal down again I got the leak which causes the loss in hydraulic pressure. The leak is via the pushrod rubber gaiter. What is causing this as the original seal and the new seal were brand new and also a good fit into the master cylinder barrel. Any ideas as to what I can do as I'm getting a bit fed-up of taking out the pedal box to try and fix problem?

Regards

Denis

Denis.
Three possible causes that I can think of.
1. The bore of the cylinder is worn or scored. But I would have thought you would have noticed.
2. The rear seal is fitted the wrong way round. (Sounds the most likely)
3. The circlip that holds the piston into the bore is missing, and allowing the piston to travel out of the cylinder

[martsam]

Purple AK,
Thanks for the reply. The master cylinder is brand new. It leaked when I put it in so I have replaced the internals anyway with new ones. The circlip is still there. I've been thinking about it tonight and wondered if the problem is that the travel on the pedal is too much such that the internal seal is passing the outlet on the master cylinder therefore allowing the fluid in the outlet to run down behind the seal and then on pedal return this is being pushed out of the end of the cylinder. Do you think this could be happening??

Regards

Denis

[Purple AK]

Hi Denis.
No I don't think the cylinder can overtravel. It will only go the length of bore and is designed to do that. It is "possible" that the rear seal was wrongly installed from manufacture. The "CUP" should face inwards.

[martsam]

Hi Purple AK,
The problem is that the original and the replacement both leaked through the end of the cylinder. I cannot think that both set's of internals were wrongly assembled.

Regards

Denis

[Purple AK]

Sorry Denis. I assumed that you had replaced the seals yourself, Following the orientation of the originals. Not replaced the whole internals, as you have. I really can't see any reason why two "effectivly new" cylinders should both leak. I'll sleep on it

[martsam]

Hi All,
Thought it worthwhile bringing you up to date with my problem. It's sorted now. The leak I was experiencing on the "New" master cylinder was due to an internal gouge on the bore. So much for buying new gear. It sealed until I pressed the pedal which forced the seal along the barrel until the gouge was met at which point the fluid pressure was released and leaked.

Thanks to all who posted solutions.

The clutch now works like a dream. Only need to get the engine running at temperature and sort out the timing and that's it. Then I suppose I'll have to put it to bed for the winter and hope next spring/summer comes along quickly.

Regards

Denis

[427scr]

Originally Posted by martsam

Then I suppose I'll have to put it to bed for the winter and hope next spring/summer comes along quickly.

Drive it all year, it's loads of fun in the snow.

[martsam]

Hi 427scr,
I had a little run in the car today with the RV8 in. What a difference. Only worry I have is the ground clearance now. The sump is only 4 inches of the ground. What is this like compared to others?? Is it sufficient?? Another thing that happened is that when I drove over a depression in the road the wheel arch seemed to contact the front tyre on the drivers side at the front. how can I sort this out?

Regards

Denis