300tdi Brake Pedal Feel

Hi all,

As per, ive had a search around for my issues but nothing is jumping out as a solution to my problem.

My brakes feel very 'flat' or 'dead' if you like. Nothing happens for the first half of the pedal, then you get a lot of resistance and a bit of brakes. Push a bit harder and you have much better brakes (that will lock up).

Now, when I first got the truck the master cylinder was leaking. So I stripped that down and put a new seal kit on topped it all up, and bled up the brakes.

They felt much better but till aren't great. If I pump the pedal whilst driving the brakes are perfect! Then I let go, and they go back to how they were?

I'm inclined to say its a brake vacuum pump issue? Any ways I can test if that's ok?

Thanks All

Sounds like either master cylinder or air in system, if servo gone then pedal would still be firm but require a lot of pressure to work brakes. To test servo, pump pedal till hard at top, keep pressure on pedal then start engine. If pedal moves down then servo is working.

What seals did you use and was the inner worn? Air in system I would say. If it were me I would buy a new master and slave, lockheed or genuine only dont buy cheap ones they are ****e.

Had the same when I bought my 300tdi.

Can tell you seeing a car stopping aharpish infront, then pressing the brake pedel for nothing to happen until you foot is nion on the floor is rather unnerving.

Mine was the discs where worn out. 4new discs, sets of pads.

Leaving the garage, went to slow down gently (like i had), full on emergency stop, smashed into the wind screen.

If its been like it with no change since changing the seals then it might just needs re bleeding.

I tested the servo, by pumping the pedal and starting the engine. And it does exactly as said. Goes rock solid, start the engine and the pedal goes down.

Its loads better than it was before fitting the master cylinder seals. But still not great. Ill try bleeding again tomorrow, and see how that fairs up. Shall keep this updated