Handbrake not working after rear caliper rebuild

[ww1dm1]

Alright, so after fully disassembling the rear calipers, cleaning most of the rust off, replacing all the rubber and reassembling I appear to have handbrake issues. The cables are fine, the actuator hooks that are pulled by the cables spin nicely until they hits their limiters (not at the same time, for some reason).

The handbrake lever goes high up. When it's at the highest position the wheels are held hard enough to prevent turning by hand, but not nearly enough to hold the car in place, I can just drive around with the lever poking at the ceiling.

I need some insight here, where could I have screwed up? Is there a special procedure to put those hooks back in place? Could I have not inserted the handbrake mechanism ring retainers back in the cylinder bore properly?

[V40DSchariot]

Hows the foot brake working with the rear wheels?
It would be hard to tell if the rear's are working adequately when the front brakes would hold the car.
To be honest my first thought was air trapped within the rear caliper's somewhere, my second thought, on purchasing reconditioned rear calipers, there was a note warning not to move the handbrake mechanism before fitting and advice if this should happen was to reset the caliper.
I'm afraid I can't remember the procedure for this, but will have a look when home if I still have the said bit of paper or if someone out there knows this procedure.

[ww1dm1]

Originally Posted by V40DSchariot

Hows the foot brake working with the rear wheels?
It would be hard to tell if the rear's are working adequately when the front brakes would hold the car.
To be honest my first thought was air trapped within the rear caliper's somewhere, my second thought, on purchasing reconditioned rear calipers, there was a note warning not to move the handbrake mechanism before fitting and advice if this should happen was to reset the caliper.
I'm afraid I can't remember the procedure for this, but will have a look when home if I still have the said bit of paper or if someone out there knows this procedure.

Well, the car stops and doesn't feel like the rear brakes are missing, though I guess it could be difficult to tell if they were. The pedal is spongy, there probably is some air in the lines, but not any spongier than it was before. Still working on that pressure bleeder.

That's interesting, why not move the handbrake mechanism? Pretty sure I've tested whether it moves a few times before fitting each of the calipers, though I can't understand what's wrong with that. Do let me know if you find that piece of paper.

[bobthecabbage]

Here you go.

http://www.midlandvehiclecomponents...._procedure.pdf

'To reset the handbrake mechanism if the lever has been operated before fitting then the piston should be turned ‘in’
using the above methods. When the piston is fully ‘IN’ then the piston should be turned ‘OUT’ half to 1 turn.
The handbrake mechanism is now set.'

I never knew the information on this sheet. I don't know why it isn't supplied with every replacement calliper!

[ww1dm1]

Originally Posted by bobthecabbage

Here you go.

http://www.midlandvehiclecomponents...._procedure.pdf

'To reset the handbrake mechanism if the lever has been operated before fitting then the piston should be turned ‘in’
using the above methods. When the piston is fully ‘IN’ then the piston should be turned ‘OUT’ half to 1 turn.
The handbrake mechanism is now set.'

I never knew the information on this sheet. I don't know why it isn't supplied with every replacement calliper!

Oh, I see, so there basically is some slack between the handbrake screw and the piston, so the piston has to be manually rotated outwards after a finishing a rebuild to take the slack out.

Golden information, thanks a bunch!

[magnuz]

If you have wound the piston right back as far as it will go, it can often take a while for the mechanism to re-adjust its self, it should adjust eventually by using the foot brake a lot !
When ever i fit new rear pads, i only wind the pistons in just enough so that the new pads will go in !

[bobthecabbage]

Originally Posted by ww1dm1

Oh, I see, so there basically is some slack between the handbrake screw and the piston, so the piston has to be manually rotated outwards after a finishing a rebuild to take the slack out.

Golden information, thanks a bunch!

I'm not sure how it works but part of the mechanism is that its a loose fit thread between the piston and handbrake. I guess that the piston needs to have some free movement back and forward whilst still engaging with the threads of the handbrake mechanism.

You aren't supposed to wind it out by using the pedal to push it out with the brake fluid. Not sure why. I have done it though as when fitting a new calliper I cycled the piston in and out a few times to try and get the small bubbles out (that hide in the mechanism).

In future I will follow the instructions though!