Offroad-Express

my mates yn67 hilux is being a right prick. the master cylinder shat itself so we replaced it. we also did the rear wheel cylinders as they were leaking. the brakes are better than before but thier not right

when driving along and you slam on the brakes the pedal goes straight to the floor. release and pump it again and its o.k.

brake pedal is fine when the engine is off.

there is no air in the system

had a quick look and couldnt find any vacuum leaks

anything i should be looking for?

make sure the one way vaulve is working in the vacume line going to brake booster from manifold. friend of mine had his in backwards and it did the same thing cant remember exactly which way it should be but someone will know on here or i can check my surfs one tonight.
chris

i had a simmilar problem in one of the old hiluxes i had and i ende3d up beening the the wheel bearings had shit out pushing th piston in the capiller back in giving it a shity pedal (cause of the movement through the hubs) and found that pumping it helpd but u might want to check out the bearings just in case

rear brakes addjusted up nicley?
disconect that load sensing valve mounted to the diff and you either move it up or down (cant remember which)
then bleed them up

good luck

yer it could be that valve il disconnect it and open it and try doing a bleed

to bleed the system push the brake bias arm up.... this simulates a full load on the rear which means the valve allows more bias to the back wheels, opening up the valve

Hmmm if its a wheel bearing it will only do it under motion, and will still give you braking just pulses when under brakes.... if its the vacum assist then the pedal will still work just be real stiff, will take alot more to push it
From the sound of your post you've bleed it several times and its nice and stiff but when you take it for a run it turns to custurd.... that say's to me you have a leak or you arn't bleeding them properly

Cheers Reece