Bloody Brake Cylinder

[Mud_Bogger6]

Well I pulled the brake cylinder out today, the entire things seized up, it spent 6 hours soaking in WD40 and still no movement what so ever, so i've opened it up and there's been water in the cylinder, so i've drained it, and applyed liberal amounts of WD40 into it, any suggestions on what to do if its still seized by tomorro afternoon??

Cheers

[Rangier Rover]

Well I pulled the brake cylinder out today, the entire things seized up, it spent 6 hours soaking in WD40 and still no movement what so ever, so i've opened it up and there's been water in the cylinder, so i've drained it, and applyed liberal amounts of WD40 into it, any suggestions on what to do if its still seized by tomorro afternoon??

Cheers

This may only work some times. Adapt a grease nipple where brake line was and press it out. A good grease gun can make 4000 Psi One of my favorite special tools.

[Blknight.aus]

nope, that works everytime... on the clutch. depending on which MC you have you may not be able to close off the fill port to deal with that much pressure

before you start that action strip everything you can off of it and leave it in warm dieso or engine oil over night. put it all in a tin and aim a pair of 100w lights at it from close range to keep it warm/warm it up

the other thing is to heat the outside of the cylinder while you cool the piston.

[series1buff]

Hi Mick

I've pulled apart many brake cylinders over the years. Usually the master cyl. doesn't tend to get jammed , it's the wheel cyls. that are the problem more often .

With wheel cylinders .. sometimes the pistons are stuck solid ... If you have cast iron cylinders , then you can heat the whole thing up with a torch ... then spray some WD 40 on it ...let it cool down ... repeat a few times . I recently tried the new Loctite product that sprays a freeze substance .. it cools down the offending part and makes it shrink > It worked on my 80" cylinders .. God they were seized solid ... Even then, I had to use a 6 ton shop press to push out the jammed cyls., after the freeze treatmment .

The grease trick works too, but it's difficult to get a perfect seal .. you have to block off the ports or holes with anything that fits , and somehow fit a grease nipple .. then you pump away with a grease gun and let the hydraulic action do the work. Its very messy .

[dandlandyman]

Series 1 master cylinders are good to dismantle, since you can take the nut out of the other end and drift the piston out. Unfortunately, though, if water has been in it for a long time you'll need a new cylinder, either a complete pattern unit or stainless resleeved with a new chrome piston. I'm not sure if they rechrome the pistons or not. Both piston and bore have to be in perfect condition (no pitting) in those (and 2/2a) compression barrel cylinders.
Hope this is of some help.

Dan.