Brake Issue need help A.S.A.P

front brakes are fine the whole system was bleed , i dont know why you would only bleed half the system

im thinking its the booster but no one has even said anything about it yet ?

You could try pulling a vacuum on the power brake booster with a hand vacuum pump, and seeing if it holds vacuum. There's also a check valve inside the short curved hose that attaches to the booster. Check also for leaks in the vacuum hoses coming off the intake manifold.

I have replaced the power booster on my '88, and my brakes did improve (maybe 8 years ago?). I did not have to disconnect any brake hydraulic lines to do this, just moved the master cylinder forward and had clearance. I did need to adjust the new booster's pushrod.

I'm sorry if I offended you I was going with the posts I saw. Yes all four wheels should be bled after rebuilding or replacing the brake master cylinder. As for the brake vacuum booster Cusser mentioned to check the check valve and leaks on the hose to the intake manifold. Just wondering as mentioned it takes a few pumps to build pedal pressure. While you did that did the engine seem to almost die or had a idle problem?

All good CAB +RIDER , no when you pump the pedal the engine runs fine still , its a diesel motor so all the vac is made from a pump not the motor

Have you tried testing the vacuum pump?

I'm not sure how to test it with out a vac gauge or what a normal reading would be ?

Here is a site that has some good suggestions to check your booster. Very informative site...

I will try that tomorrow and report back

i tried the test's in the above link and it seems that my booster failed all of them

i cant seem to find another diesel brake booster any where to see it that's the problem and don't wanna put a petrol on it as im pretty sure there different and the petrol on doesn't have the little sensor in it my diesel one dose