Hi chaps
I have a kit car that I have fitted a cossy servo, the problem I have is if I plumb it the way it is shown in the work shop manual I cant get the back brakes to work, When I switch the egnition on to start the pump and open the passanger side bleed nipple the pump pumps fluid out If I swop the either front brake pipe for the rear brake pipe front the and turn the pump I can pump fluid out of the rear calipers and get a brake but the one I have swoped with will not work I just carnt work it out. It should be plumbed the outlet nearer to the front goes to the passanger side the middle one goes to the rear and the last on goes to the drivers side thats what it says in the manual but it will not work, I have tried lifting the rear calipers so that the bleed niple is on top I have tried pressure a bleed kit I have bought another cossy servo and pump but it still wont work any ideas please. I have not fitted the abs module does this alter the way it sends the fluid to the brakes
Paul.

Paul

 

It's a bit difficult to understand what you've written (an edit may be worthwhile), but I think what you're saying is that you can only get the pump to pump fluid out of the rear brakes with the ignition on. If this is the case, then it's correct - the ignition should be switched on to bleed the rear brakes, and the fronts need to be bled in the old style fashion.

 

When I bleed the brakes as it says to in the work shop manual I get good front brakes but no rears, If I swop the pipes coming out of the servo lets say the pipe nearest the front of the car [passanger side] with the middle pipe [rear brakes ] and switch on the pump I get good rear brakes with pump pressure after bleeding, this leaves me with both back brakes working and the driverside working but no passanger side brake.
I thought it was the servo unit so I replaced it with another and the pump.

 

Hi I have fitted the same system to an electric milkfloat.I too had problems bleeding the system,the very same as you have descibed.
You do not need the ABS module But you do need the valve block that the module plugs into.Plumb the valve block into the system and bleed the complete brake system the same way that you would on a normal conventional brake system.
Paul

 

cheers paul
just made my day.