Thread: trouble bleeding D1 Rear Brakes

Has the rear flexy hose been damaged?

Take it off and see if you can actually blow through it...

Jc

Originally Posted by crash

Working on a D1 which had lost its brake fluid due to a fault on the passenger front wheel. Problem has been fixed.
Now I can not get any fluid to the rear brakes. I have fluid at both front brakes but can not get the rears bled.
The rear bleed screws are free of any debri.
The foot brake has little travel and is quite firm.
Have bled the lines at the master cylinder.
I am at a lost as to what to try next.

What year model is it, the front discs on 93's have 2 brake lines to the caliper and 3 bleed screws, one at the top out side which you may not see with the wheel on.
There are 2 circuits, the bottom piston in the front calipers is part of the "Secondary Circuit" which is connected to the rear caliper through the Tee piece and the "pressure reducing valve".
The "primary Circuit" from the master cylinder pipe closest to the Booster goes only to the top pistons in the front calipers.
If you have this setup you need to bleed all 3 nipples on the front calipers in correct order, let me know if this is the system you have and I will send you the workshop manual page on how to bleed this system properly.
Remember this system has 2 brake lines into each front caliper, Regards Frank.

Its a 94 model V8, only one brake line to each front wheel.
There is no visiable damage to any lines.

On the passenger front guard is a "distribution" block - one line going into the bottom of it and 3 lines exiting form it - 2 side by side towards the rear of the vehicle - which look to be going tot he front wheels and a single line towards the front that appears to be going to the rear brakes.

As mentioned in OP, the fronts have been bled and are working.

ABS block ??

Originally Posted by pop058

ABS block ??

Is that what I described above?

could be

the master cylinder could be locked over on the secondary ciruit and is not bleeding up.

crack the line for the rears and check that you can get it to bleed from there.

if you have the brake proportioning valve if it gets over centered it will stay closed off and not give you flow for the back brakes.

flex line and then the T piece.

Black Night I think you are right about the proportioning valve has gone over centre.
It is NON ABS.
Both lines from the master cylinder have been bled to the proportioning valve.
Their is fluid going to the fronts, but I can not get any fluid out of the connection at the proportioning valve going to the rears.

How can I get the proportioning valve back the other way?

I usually pull it apart and clean it then lube it and that works.