clutch problem

[redthing]

I have mentioned this before but, nobody came up with an answer so, I'm trying again! I have a very infrequent clutch problem ( happened twice in 6 months). I'll be driving along happily and suddenly, the clutch will start slipping in whatever gear I happen to be in. The clutch pedal goes rock hard although I can still push it to the floor and change gear. this will go on until I pull over and switch off. Five mins later, I can start up and carry on with my journey as if nothing has happened.
My son thinks that something is sticking on the input shaft but I would welcome any input. At all other times, the clutch behaves perfectly. I'm confused!

 

[solarman216]

difficult one this, I can think of several items that could cause this but without feeling it for myself cannot say for sure, first item is renew the flexi hose these are known to come apart inside so acting like a one way valve, stopping for a while and it could slowly drain back and be normal again for a while, for the pedal to go hard this sounds reasonable, the next item is a slave cylinder that is seizing perhaps with heat, again hard pedal will happen, the next is the pressure plate this has a diaphragm spring and wear ridges can form that can jam it, rare but happens, but this is unlikely to cause hard pedal, and last is the thrust bearing and fork wear causing it to tip could jam it but less likely, Rick

 

[kitchenman]

A friend had that problem garage fitted new clutch, problem still there:doh
A garage who knew what they were doing found the problem to be a non return valve in master cylinder.:clap
Next time it is slipping try what they did, open the bleed valve on the slave cylinder, if fluid gushes out you have somewhere to start
dave

 

[solarman216]

that is a good point kitchenman, Rick

 

[redthing]

Many thanks guys...