brake pedals creeps down,,,,,,,mot fail

[scottie]

failed mot on brakes, couple of pipes h/brake and tihs

"brake pedal creeps down when held under preasure"

any ideas how to cure this? i thought it must be the master cylinder but afetr finding it hard to get the right one the guy in mty local shop said it might be the servo pump on the back of the alt

anyone else had this?

scottie

[Guy88]

either master cylinder or wheel cylinder

what van is it

[scottie]

its a 96 transit 80 2.5

the rear cylinders are bone dry as i checked these while checking the shoes, it doesnt seem to do it while the engine is off this is why i thought the guy might be right about the servo pump, ive got another m/cylinder on order, going by the pic in the book it looks the right one

scottie

[Guy88]

If the pump failed the pedel would go hard

[bazw]

just been through this with my splinter
5 master cylinders and a gallon of brake fluid with the wife complaining about her legs when bleeding the brakes and i fixed it when i took the wheels off and seen how thin the discs were


vents are not supposed to have a sharp knife edge on the outside are they

so new discs on and a quick bleed and right as rain

i guess the pistons being right out meant it would not push the air bubbles out from the back of the pistons when i bleed it

i now have a 4 output MC and no ABS or load valve and a pipe to each wheel but will return to normal later

i can lock all wheels now though

[scottie]

i put on new discs for last mot, but this year the rear shoes are right down, almost to the metal, will do the shoes and h/brake cable first then see what the pedal is like

scottie

[scottie]

right , getting desperate now, been at the brakes since 10AM, fitted new m/cylinder,shoes,discs,pads,h/brake cable, burst one rear cylinder so replaced that, all bled up and the pedal still creeps down with the engine running,

anymore ideas?


scottie

[gemini]

are you getting air when bleeding the brakes

[scottie]

no, none atall


scottie

[Smooth Hound]

you must have missed something, if its creeping down, it can only be master, or wheel cylinders, or a leaking pipe, how is your fluid level , does it seem to have lowered at all, or is it the same as it was

[Smooth Hound]

try a one man bleeding kit if you cant find another problem, you could well have an air lock

[scottie]

only thing left to do was the other wheel cylinder, which was bone dry, cahnged it and it was better, so had to take it for its retest at 5pm and it passed

i thought it was a good thing only failing on brakes and a number plate light but still cost me a fortune

scottie