Xk150 brakes binding on

Hi again, I have restored my xk150 over sometime and am driving it more and more as a shake test, all is fine and I’m very please and impressed with the car , I do have a problem with the brakes in that they bind up after a couple of pushes ,when I pull away they feel stuck on but suddenly free up, I have all new brake lines ,front 4pot calliper’s new, cylinder’s are new, I can not see why its doing this ,has anyone got any ideas. Thanks Chris

Dear Chris

I have had the same problem…
I have put Zues 4 pots on the front - but mine does not have the Vac tank as its an early one.

So this is what I did…

Disconnect the brake servo and plug the vacuum end that comes out of the manifold or alternately I used a pair of mole grips and compressed the pipe…. go for a drive and see if it binding – but you will need to apply a fair bit of pressure on the peddle.
If the brakes don’t bind you could have 2 problems – 1… the servo is broken or the one-way valve is broken and simple first quick fix is to put in an extra 1 way mid-way in the pipe.
If it still doesn’t work you now have a potential 2 problems – either the servo is not working or the master cylinder is sticking.
I replaced my old type servo (that was newly reconditioned) with a new type unit (keeping the old recon as a spare) and that made a huge difference, but I too still get a little bit of brake binding… but frees off quite quickly – but gets on my nerves…
I put a new brake master cylinder on as part of the restoration (cheap), but it’s one of the replica types and I think they are a bit rubbish – I am contemplating putting one of the Lucas type that are £200.00…. to eradicate it fully……hope it helps
Oh, and check you have the correct end float in the foot peddle

Thanks for the reply, I will try this out next week. will let you know . Chris