Rear brake problem

[hilly64]

Got no breaking on nearside rear brakes... So mot man pointed out but truck was fine driving down to station however what has happened a couple of times previously is that the pedal went stiff and sat up a bit but after a hard brake i felt it release and go back to normal travel/ feel

Any road up when i picked up truck after mot pedal felt hard and up somewhat. Took drums off got no movement on shoes but check both sides and they are the same. Got no fluid out bleed nipple on nearside drum so did a bleed at inlet to valve and have fluid but nothing on outlet side so guess theres a fault with it

Are these prone to blocking/problems?

Is it a simple exchange?
Links look very coroded do these just need a clean up and refit?
Is there a reason behind complex bends in push rod between valve and axle?

Cheers for any advice

[TonyN]

The rod is just shaped to miss exhaust when the rear axle is at max bump off road. It should be mostly straight with a curve at the axle end.

Wheel cylinder is only two small bolts. It could be jamming, not really anything they are 'known for' but can happen.

Did the MOT man pass it on the handbrake? A wheel cylinder/bias valve rod problem won't effect the handbrake readings, only the normal braking on pedal.

[hilly64]

advisory on handbrake 60%

the truck has had full toyota service history up until i got it 4 years ago and it shows, all clean and tidy in drums which came off easy

wheel cylinder seemed ok and pistons free but nothing at all out of bleed nipple

when i went to compensator valve and cracked connectors got fluid at inlet but nothing from outlet pipe - am i right in thinking its dual feed with one outlet splitting to each axle??

about to order valve so can get fitted at weekend (feels dodgey driving with only front brakes so being very cautious)

the only niggle i have is that when mot done did have braking at one wheel and seem to recall when replacing some rear brake pipes that it was a beatch to bleed something to do with how the reseviours are set up??...is there a technique to bleeding?

cheers

[hilly64]

UPDATE

new valve sorted the problem but what a beatch to get the old one off, fully siezed on requiring grinding and redrilling bracket and for anyone else having problems bleeading the back brakes - make sure you bleed the compensator valve first and thoroughly, thought i had but could not get rid of air until I went back and gave it more stick

[Mr Malleenos]

Hi, glad you got your brakes sorted! I've had exactly the same problem with my brake pedal. I would have moderate braking then if I pushed hard the pedal would "come un-stuck" and go down to the floor and I would have full braking. Now, after the truck has been sat for a couple of months because of a steering problem the pedal does not go right down and feel there is only front brakes..(I haven't had a look yet though). Although when I had my MOT a few weeks ago he said there were no rear brakes but then he tested them again at the end of the test and they were perfect!
Question being did you just fit a new load sensing valve or did you have to do any adjusting too? I just have the uprated 2'' springs on the rear. (kzn130)

Cheers.