fatmike

iTrader: (4)

hi guys got a bit of a strange 1 my m8 has got a s2 and his brakes wernt the best so he changed them to cossy stuff but when we went to bleed them he just couldnt get the brakes pressure back so we changet the mastercylinder twice no improvememnt changed the brakes back to the s2 stuff no diffrence and even fited new rear cylinders and shoes still no beter eney ideas? also the abs is removed.

Moonie

Are the rear brake load apportioning valves still fitted? If so, how are you bleeding the rear brakes?

You need the wight of the vehicle on its wheels/suspension to allow fluid to pass through to the brakes. If the vehicle is jacked/supported under the body with the suspension hanging down you will never bleed the rear brakes as the valves will stop the fluid flow.

fatmike

iTrader: (4)

yes still fitted mate using the old fashon sit and pump whilst sum 1 open and closes the bleed naple off also bleeding the drivers rear first

fatmike

iTrader: (4)

if i removed the load valves would i need a bias valve to replace them ? i do get sum fluid out of the blead niples just a drible not enoughf pressure

Chris69

another method is to support the rear of the car on its suspension so the car sits level while you bleed with the wheels off- its how i did mine and it worked a treat.
i had it on axle stands with the suspension hanging down before that and i had the same issues your having

Moonie

Yes, you would need some way of reducing the pressure to the rear brakes to prevent them from locking with weight transfer to the front if you removed the standard load valves.

Sounds like your either not jacking the car up under the suspension or the load valves/linkages are faulty or seized if there is only a dribble of fluid coming from the rear bleed nipples.