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MG MGB Technical - Clutch advise

Hello all,

Some clutch advise needed please. No resistance in clutch pedal, can't select gears with engine running. Clutch reservoir empty, some fluid collected in drip tray. No sign of master cylinder leak....does this point to slave cylinder leak/failure?
Thanks, Clark.
C Egbert

Everything that you've posted points to a leaking slave cylinder. You may have a leaking clutch slave hose, but this is rare since it has no moving parts to wear out. RAY
rjm RAY

Thanks Ray. I can't check the slave until the car is out the garage. Would it be worth changing the master cylinder at the same time (both 36 years old) or leave well alone?

C Egbert

When I changed my master I certainly changed slave and hose at the same time, not sure I do it the other way round though if the master was otherwise OK. You should certainly change the hose when changing the slave, and that is where you may have problems as the upper hose fittings are a beggar to get to and can be well rusted. If you give up on that and decide to keep the hose you will almost certainly find when screwing a new slave onto the old hose that it no longer lies flat against the bellhousing, but you should not fit it like that putting a twist in the hose. You may be able to get away with putting a second copper washer in, if the slave just needs to be unscrewed a bit to lie flat.

AFAIK the square master is NLA, they seem to have round clear reservoirs now. You should refill the system and determine where the leak is, before changing parts though.
PaulH Solihull

Thanks Paul......I've still to check exactly where the leak is but its in the area of the slave. Will fit new hose as well. New brake master clinder fitted a couple of years ago is round and clear, expect clutch one is the same as you say.
C Egbert

You should change the soft hose, and the dust boot on the tranny, along with the clevis pin, as well.
I would also change the push rod, as they are relatively cheap, and tend to get worn....
No need to buy a new slave, unless the cylinder is "pocked" or badly corroded...
The kits on these usually work pretty well.
E.B. Wesson

Physical wear of the linkage at the slave end is not a problem like it is at the pedal end, the hydraulic system takes up all the wear in that just like it does in the release bearing and the friction plate. At the very least you will need a seal, but the cylinder wall on the air side of that is likely to be corroded, and as the release bearing wears the seal will come into contact with that. It's not really worth fiddling about with the seal and the boot IMO, just swap it and be done with it.
PaulH Solihull

This thread was discussed between 27/08/2011 and 29/08/2011

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