Thanks for you help we have taken it down to a mechanic and he is having a look, but would the brakes fail if it does not get sorted. thanks

Sam H, hello.

IF IF IF l am correct, and the problem IS your power brake booster, then NO your brakes will not fail.
The booster is a big vacuum tank. The vacuum tank makes it easier for your foot to push the brake pedal downwards. Power brakes!

Without the booster (or if the booster has a vacuum leak) it is just harder to push the pedal down. YOU STILL HAVE GOOD BRAKES :)

l am sorry if l alarmed you..Trevor Trillion

Trev is right- you should have enough power in the slave cylinder hydraulics to slow you down. Just take it easy- and use the handbrake- very gently! when you need to slow.

Driven a ton of times with minimal brakes. Done it even in an old Rover V8 3500. Very scary= 2000lbs hippo on rollerskates.