Thread: bench bleeding Land Rover CB type Brake Master Cylinder

Gentlemen,
I am looking for a procedure and tips on bench bleeding a CB style Brake Master cylinder. I have read that Brake Master cylinder needs to be tilted up at the front to get the air out, and that is not possible with it installed.
I get how they bench bleed modern Master Cylinders with open chambers and a removable lid, but our CB style have a basic port in and port out configuration.

I assume that I need to maintain a supply of brake fluid to the input port and watch for when bubbles cease on the output side, just as you do with wheel cylinders.
I'd appreciate any advice or tips on any of this.

regards and a happy pre-Christmas to all.

regards
Jeff

Hey Jeff,

Doubtless you will be getting better advice than mine once more replies roll in - but I might as well try to help(!)

I haven't actually bled a CB master cylinder in decades, as my IIA now has a CV. I remember an ex-army mechanic telling me years ago that they used to raise the noses of vehicles (a lot) to tilt the master cylinder as you suggest during bleeding.

I know that CB-types are a bit more fiddly than CVs....but if you do end up trying to bleed it in situ when it's fitted to the vehicle, a little trick I use with my IIA might help you: rather than trying to bleed once all the shoes, springs and drums are fitted, I place a G-clamp on each wheel cylinder to eliminate any potential "soaking up" of pressure caused by springs/shoes expanding to meet the drums, bleed the system and then fit the brakes. It works a treat.

I hope that helps.

Merry Christmas!

John