Clutch slave/master cylinders

[Shaun II]

What grease would normally be used in these parts, I think there is some kind of compatibility problem with normal greases and brake fluid? I have rusty cylinders that have then damaged the seals, bit of a pain really.

[mudhut]

You must not have any contamination of brake fluid by mineral oils/greases - it makes the seals swell.

If the cylinders have corroded you might try honing but unless you can get rid of all the corrosion, I'd say the cylinders are scrap. They can be bored out and fittted with stainless steel sleeves to the original diameter though. This could cost more than a new slave, but maybe not more than a new master.

Piston seals should not be lubricated with anything except brake fluid. On the "outer ends" of the cylinders, where the pushrods poke through the rubber outer seals, use rubber grease (red in colour).

[Shaun II]

Rubber Grease it is then, merci.

[Arthur]

Master cylinders are cheap, and considering their duty, any doubts at all, throw them away.
There should be nothing but hydraulic oil in contact with any of the internal seals, up to and including the piston seals and backing rings (if fitted).
The red grease is for the ball end of the pushrod, and for the rod penetration through the rubber dust cap - no contact with hydraulic parts at all.

Arthur.

[SUSIT]

Master cylinders are cheap, and considering their duty, any doubts at all, throw them away.
There should be nothing but hydraulic oil in contact with any of the internal seals, up to and including the piston seals and backing rings (if fitted).
The red grease is for the ball end of the pushrod, and for the rod penetration through the rubber dust cap - no contact with hydraulic parts at all.

Arthur.

Arthur you must be paid far to much!!!! My 7/8 clutch M/C was £98 not including delivery :( but I do agree if in doubt bin it :)

Stephen