3 replies to this topic

[austinmini1963]

Hi there,

I am having some trouble bleeding my rear brakes on my mk1 mini. It seems as though there isnt much fluid coming out of the rear while bleeding, is this normal? Is it to do with the compensator valve? Do I need to give it a secret handshake before it will work?

My car is a 63 mk1 with single leading shoes, its just coming near a roadworthy state after being off the road for many years. All the brake system has been replaced apart from the compensator which has been refurbished. The system was stood empty of fluid for many months and I am using automec dot 5 fluid.

Many thanks, Tom

[Cooperman]

Make  sure the bleed screw on the wheel cylinder being bled is fully open before starting to push the pedal down. If any pressure builds up in the system before the bleed screw is cracked open, the compensator valve will shut off and isolate the rear brakes.

[Gremlin]

Make  sure the bleed screw on the wheel cylinder being bled is fully open before starting to push the pedal down. If any pressure builds up in the system before the bleed screw is cracked open, the compensator valve will shut off and isolate the rear brakes.

I'm guessing this is true for if you've got a balance valve on the bulkhead as well

[dklawson]

As Cooperman said, any pressure on the subframe mounted valve will cause its spool to shift and block fluid flow.

 

Try the following.

Loosen the hard line going into the rear valve.  Slowly push the pedal down (and slowly let it up) until you see fluid coming out of the open pipe.

Reconnect the pipe and loosen one of the hard pipes going to the rear brakes. 

Again, slowly work the pedal.  It should not take long for fluid to come out.

Secure that pipe and repeat the process on the last pipe.

Once that is done, open the bleed nipples on the rear wheel cylinders (wide) and make sure the reservoir is topped up.

Give the system some time for fluid to start coming out of the bleed nipples.  Close each one once fluid starts coming out. 

Finally, bleed the system using the 2-person flush method working the pedal SLOWLY.

 

Also, remember that a properly adjusted rear brake is not one where the wheel will freely spin.  Elevate a rear wheel, tighten the adjuster until you can spin the wheel by hand, hear shoe drag, and the rotation stops in 1 revolution or less.  I have never worked on single leading shoe brakes so others will have to tell you what is correct for them.

 

Enjoy your Mk1 !