Currently working on Toyota Masterace Surf. Having problems bleeding air out of braking system. Procedure currently adopted is
Bleeding order from furthest master cylinder to nearest. Brake pedal remains "spongey" and warning lights comes on when brake pedal is pumped!!! Help!!

- (#3994) Graham Harman, 26 Jul 02

see post in your previous thread...

- (#3997) david miller, 26 Jul 02

If you are simply pushing the pedal up & down, whilst a colleague is opening & closing the bleed valves at the wheels, then this is very bad practice. Chances are that you have now damaged the brake master cylinder, by pushhing the piston into unchartered territory, remember it only usually moves a few millimetres in everyday use, now you are pushing it to the end of the bore, this has a habit of damaging the seals, or even flipping the leading edge inside out. Best practice is to use a pressure bleeder to force the fluid through the system & thus push the air out, however with the restricted access to the reservoir on the Townies, a better method might be to use a vacuum bleeder on each wheel cylinder/caliper in turn to literally suck the fluid through the system, whilst keeping the reservoir full, and thus suck the air bubbles out. This type of kit is quite pricey, but a Rover dealer only charges £25 for a fluid change, so visit you local garage & ask if they can vacuum bleed your vehicle & see how much they want. Hope this helps, Rob.

- (#3998) Rob Drinkwater, 26 Jul 02

Sounds like an air lock somewhere, this will compress and draw fluid into the master cylinder giving a low level light. Once released the air expands and puts the fluid back, check whilst bleeding and getting the light on, by holding the pedal down and looking at the fluid level. Have you bled the load sensing valve at the rear axle (thanks to David Miller for that thought)? Brakes are a thing not to play around with if you are not sure. Rob's advice may put a stop to the problem (sorry could not resist it).

- (#4002) clive, 27 Jul 02

Yes but do remember there's a vacuum sensor too. If the engine's not running, the light will come on after 3- 4 pumps of the pedal...

- (#4003) david miller, 27 Jul 02

Thanks for the info.. shame I didn't read Robs input before I started! I have got brake pedal quite reasonable now, just looked at rear linings- really low, maybe the warning light is coming on due to this.

Cheers!

- (#4011) Graham, 27 Jul 02