MOT failure!! rear brake has no pressure Help!!
 

Hi all,

My 900ssie has just failed its mot due to the back brake not working - it has about 10% pressure - eek!.

I'm hoping it may just be air in the system as i don't normally use it ( could this happen??) but either way i have to bleed it and a mate suggested i reverse bleed it to see if theres air in the slave cylinder..

Would this be a good idea or has anyone got any ideas or little fixes that could source the problem or better still cure it without bleeding the system?

Thanks in advance

ant

USD caliper sir???

If so I'd suggest unbolting it from the mount - pushing the pads/pistons right into the caliper and then putting a suitiable block of wood or something between the pads.

Then try and get the caliper higher than the master cylinder - pump the pedal a few times, crack the bleed nipple (WITH CARE AS IT MIGHT SPURT!)

Repeat until hard......sorry, the brake NOT anything else :)

Cheers - Frank

Ooh err missus...!!

cheers Frank!, ill give that a try.

Ok, been trying to bleed the air out all night i get so much out and still more air. Can't find any leaks and ive completely drained the system,started again, got a small amount of oil coming out constantly but no where near enough to create any pressure at the brake lever.. so i start the process again, pump the lever,hold it, open the nipple and get air coming out and then a small amount of oil again.

No change in the amount if air though and ive repeated it countless times.

Anyone got any ideas???

Thanks

ant

Bad luck - sounds like a seal may have gone.

I'd suspect master cylinder first rather than a caliper seal but I stand to be corrected. A full strip down sounds in order and the master cylinder is where I'd be starting.

Frank

As Franck said, if your rear brake in USD mounted, you need to reverse it when bleeding it. I don't think you need to have it higher than the master cylinder (I never had to anyway...) but for sure you want the bleeding bolt to be at the top of the caliper...