300tdi soft clutch - update

Its the master cylinder. If fluid leaks past the seals in the master, it goes back into the reservoir. If fluid leaks past the seals in the slave, it leaks out. as you have no visible leak, it must be the master that has failed.

Having said that, it is wise to change both, as they have both done exactly the same amount of work, and if one has failed, the other wont be far behind it.

"SimonJ" wrote in news:dqg5lk$rif$ snipped-for-privacy@nwrdmz02.dmz.ncs.ea.ibs-infra.bt.com:

I was underneath today and there is weeping from the drain plug hole in the bell housing. Not much but enough.

Thanks everyone. I removed the master cylinder today and the new parts (both cylinders) arrive tomorrow.

Derry

You need to stamp the damned thing while it works! The sudden and higher than usual pressure expands the seals just enough extra to 'repair' it for a fair period extra. Had this tip from a local engineer who said it worked nine times out of ten when I actually went in to change cylinders. I am a good customer so he had no illusion of lost profit ;-) Worked for me and gave another two years of hard use before seals actually started to leak externally.

Huw

Was it weeping brake fluid? In which case you are right to change the cylinder but I can't see why you would change both. You Scottish farmers must be made of money LOL

Huw

On or around 16 Jan 2006 21:38:55 GMT, Derry Argue enlightened us thusly:

Also, you have classic master cylinder not-returning symptoms - lifting the clutch pedal with yer toe helps it return. If the master cylinder doesn't return "home" it never gets any more fluid from the reservoir. The master cylinder return is by means of a spring inside it, so anything interfering with the movement of the piston stops it.

when you refit the master, make sure the pushrod is adjusted right. You need small amount of play such that when the pedal is fully up (it should have springs inside the cab lifting it) there's no pressure on the MC pushrod. This ensures the cylinder piston gets all the way back to the home position.

Austin Shackles wrote in news: snipped-for-privacy@4ax.com:

Been there, done that! Had that problem years ago with a Renault 5 van. Set off from 40 miles north of Inverness for sheep sales on Anglesey, North Wales. The clutch stopped working at Inverness. I was not amused, especially as the job had been done by a local garage to make sure it was "done properly" and I had to hire a car to get me down there in time for the sale next day. In all adjustments, I now always measure what has been taken out and make sure the replacement corresponds.

I've done a Google and see that bleeding the system from the bottom is recommended as it was for my old 504's. The trick of using a pipe from a brake bleed nipple is pure genius but as I am single handed I'll probably go with the oil can method through the slave cylinder.

I think the logic about replacing both cylinders is that (a) the seals in both cylinders are the same age so presumably in a similar state of decrepidation, and (b) the fragments of rubber etc from the worst cylinder will hasten deterioration in the second.

From posts here, it does seem that both cylinders are either out or on the way anyhow. (Non-return of clutch pedal = master cylinder failure, weeping from drain plug = slave cylinder failure). There is logic in my madness but thanks for the warnings.

Derry

How's the replacing going Derry?

Regards

William MacLeod

" snipped-for-privacy@macleod-group.com" wrote in news: snipped-for-privacy@g43g2000cwa.googlegroups.com:

Finito!

Seems OK. The test will be my regular trip to Bridge of Allan in a day or two - 380 miles!

Thanks for all your help.

Derry

Excellent. I can stop looking for green 90s with failed clutches at the side of the road ;-)

Regards

William MacLeod

" snipped-for-privacy@macleod-group.com" wrote in news: snipped-for-privacy@g14g2000cwa.googlegroups.com:

Just be careful you don't run down the poor old bald fat bloke in the middle of the road trying to flag you down! Everything is working fine at the moment and that is always a bad sign... :(

Derry