7 replies to this topic

[needhelp!!]

Hi there, quick intro.  My older brother was given a 1978 Austin Mini 1000 for his 16th birthday years ago.  He drove it all through high school and when he went away for University it was stored in a climate controlled barn.  For the past 15 years it was not driven or started.  His 40th birthday is this fall so I got the car out of storage last month and my dad and I are getting it running again for him.  Everything has been going well until I topped up the brake fluid and when I stepped on the pedel there was fluid coming from this fitting that I have pictured.  I removed it and noticed that there is a groove in the threads.  Is this the brake failure switch?  Does the leak mean that the master cylinder needs to be replaced?  Any help would be appreciated!  swtich1.jpg   22.86K   0 downloads  switch2.jpg   35.43K   1 downloads

[Bat]

Hi,

It is the warning switch, my guess is there should be a rubber washer on it to keep it sealed. The groove looks as though it is supposed to be there.

Cheers 

[Spider]

If it's leaking Brake Fluid via the switch, the short answer is that the Master Cylinder needs an overhaul.

 

Where the switch screws in to is normally a 'dry' space on to the shuttle inside. The shuttle itself has O rings either end to seal off the fluid.

 

This might help;-

 

[cal844]

Try fitting an O ring around the switch connection end of the threads and refit, it should atleast allow the brakes to bleed up

[needhelp!!]

Awesome, thanks for all the tips guys!

[Swift_General]

As Moke suggests, brake fluid should not be there, hence only a plastic thread. The purpose of the switch is to detect when one of the circuits fails. Fitting a washer or the like will only temporarily mask the problem which will remain. Master cylinder needs a rebuild or replacement.

[Rorf]

Moke is 100 % right, there should be no fluid coming out there. These master cylinders are now redundant so you might have to replace it with the newer version.

 

I believe overhaul kits might be available but you need to strip the MC down to check that the bore isn't scoured or rusted.

 

Standing this length of time with the original brake fluid will probably entail replacing all the brake and clutch cylinders.

[Bat]

Hi,

You might be better off fitting a new master cylinder rather than pump bits of rubber seals all around the brake system.

Flexy hoses collapse internally so probably worth changing them too.

Cheers