Hydraulic Brake Cylinders

[Alan]

My Special has hydraulic brakes, and as it’s been standing a while, the wheel cylinders are stuck. As they do.  My problem is they are the side valve Morris minor ones - aluminium, not steel, and not interchangeable. I’ve tried all the Morris Minor parts stockists and nobody has them. Anyone got any ideas? I know I could update to the newer parts but I don’t really want to- the car has been like this since the 1940s.

[Chris KC]

Best suggestion I have Alan is Beaulieu next weekend. After that we're into winter...

[geoffharrison]

Alan , try PastParts in Bury Edmunds .I believe they offer a resleeving service ,subject to the amount of wall
thickness available.

[Charles P]

Resleeving? 


http://www.pastparts.co.uk/index.php?rou...ation_id=8

Charles

Edited to add: Great minds think alike Geoff

[Bob Culver]

For the last 50 years my cars have been a Javelin and then a Minx. Both have alloy cylinders, latter Minor style with the lever allowing water to enter. Weep slightly every few years. Most resleeve but is tricky and expensive  with the lever type and slot. I have simply smoothed with fine paper and replaced cups. Surface is not perfect but survives for years . the Javelin ones(with no external seals) regularly stuck due the cyl plating wearing through. Cleaning them removed remaining plating and made worse. I just tinned them and then OK for years!

[Zetomagneto]

You can get them apart by putting a grease nipple in the union and using your grease gun to pressurise, then, as suggested get stainless sleeves put in them

[Alan]

Thanks, guys. So far I’ve got one apart and the bore looks ok. New seals might fix it. See what tomorrow brings.

[Chris KC]

Assuming seals are replaceable warming might help, but I'd drain any fluid before using a flame as it's highly inflammable. I should have thought if you can get the units apart in one piece then a gentle clean-up with very fine emery and a new set of seals would get you going (or rather stopping) again. I'm not sure how much pressure you could generate with a grease gun but the hydraulic system itself ought to be able to generate a fair bit. For goodness sake if you use grease or any other process that involves mineral oils make sure every trace of it is removed before refilling with brake fluid.

[andrew34ruby]

I seem to remember a grease gun will develop pressure over 2,000 psi. So I guess this is far more than can be created by the master cylinder.

[Chris KC]

Don't know about a Morris Minor but modern brake systems can hit about 200bar = 3000 psi.