Just took the Traveller out of the garage for a quick drive this arvo, however when I pushed the brake pedal gently it went straight to the floor! when I then pressed it quickly it hadfull pressure. I've tried it several times and it will do it repeatedly.

There are no obvious leaks or loss of fluid so I can only think it's a master cylinder problem.

Any ideas guys before I rip it out?

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1965 Morris Mini 'Woody' Traveller

probably not the master cylinder, cos it wouldn't hold any pressure, more likely some air has gotten into the system, or a brake line has turned into a balloon

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did I tell you that I won a trophy?

Clamp off all brake lines and put your foot on the peddle, if it slowly sinks its the master if not start checking the wheel cylinders

steve

Cheers guys, I'll have a look in the morning.

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1965 Morris Mini 'Woody' Traveller

Master cyls can do what he`s saying & when they do that , then it`s normally cause it`s internally by-passing, that is fluid will pass through the worn primary cup when pedal is gently pressed, but shove it hard & the cup expands greatly under the high pressure & seals (for now)

easy-peasy

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

Has it been recently re-kitted???

I have seen this one - there are 2 sizes of master cylinder 0.70" and 0.75"

If a large bore master cylinder AND it is litted with the wrong [smaller] punger rubber, then on gentle pressure the fluid just leaks around the plunger rubber [still within the cylinder bore] and the pedal goes to the floor. But if you stab the peda hardl, the sudden pressure forces the cup out against the bore sides and pressure is maintained [while you have your foot on]

FWIW
Dat