Grease to free off brake cylinders.

[MarkyB]

How does one go about it?
With a grease gun.
I assume a grease nipple needs to be fitted, will one go in the bleeder hole and how do you block the holes for the pipes?

[JOWETTJAVELIN]

M/cyl or wheel cyl, Marky? Grease or oil should not be allowed to enter the braking system or even get near it... If the wheel is locked you could try tapping the drum with a hammer or even remove it.

[MarkyB]

Front wheel cylinders.
The rubber parts will be replaced, so not an issue.

[mike.perry]

Remove brake drum and shoes and clamp working cylinder. Push hard on brake pedal and hopefully cylinder piston will pop out. Soak in brake fluid, nothing else.
Not worth replacing rubbers, replace complete cylinder

[bmcecosse]

I have done this to free off an expensive caliper - not sure if it's worth it for a wheel cylinder. But I found when I removed the nipple attachment from my grease gun - the thread on the extension shaft was 3/8" UNF - a precise match for the caliper/cylinder thread. So - attach to the cylinder - block the other hole with grease nipple - and pump away! And as you know - you will need to thoroughly degrease it - wash with brake fluid - fit new seals and some 'red' brake grease when you re-assemble.

[MarkyB]

Thanks Roy.

[JOWETTJAVELIN]

Use meths for cleaning brake parts. Of course, no abrasives on internal surfaces.

[MarkyB]

I think whoever said clean with brake fluid may have meant brake cleaner.
Degreaser followed by meths should get rid of any greasy residue if any worth saving turn up.

[drivewasher]

Use meths for cleaning brake parts. Of course, no abrasives on internal surfaces.

The bore of cylinders should be HONED if they are glazed or have slight wear marks or the new seals will rapidly wear. A honing toolcan be purchased for this a great big un for combustion bores or a tiny baby one for brake cylinders master and slave. Although as said unless you altredy hav a honong tool probably not worth it for wheel cylinders

here's one not as costly as I first though: http://www.ebay.co.uk/itm/1-1-8-BRAKE-P ... 3a81dcd25f

[MarkyB]

Thanks drivewasher , honing brake cylinders is much more common in the USA from what I can understand from various forums.
For £7 I'll have a punt as I can't see a problem with the idea as long as not too much metal is removed.
Do you know if they are used "dry"

[drivewasher]

On brake cyls I would use brake fluid. Keep cleaning the honing stones. Up and down movement will give a nice even "criss cross pattern"
Then buff up with VERY fine wet n dry and then a metal polish to get a mirror finish

[rayofleamington]

freeing up and adding a seal kit to a seized Minor cylinder is usually a false economy - new cylinders are not rare or expensive. a new cylinder is usually cheaper than a new set of shoes if/when the repaired cylinder leaks again.
Minor cylinders are prone to pitting, and that's terminal although not immediately apparent when rebuilding.

For a really rare or expensive cylinder / caliper I understand why honing (or sleeving) is done, but for £15ish I wouldn't contemplate it. I have of course done it many times in the past - especially when I was younger & had a lot to learn.
e.g. Re-honing with a brillo pad did take away much of the visible dirt and rust but really wasn't a solution.