Club 80-90 Forums

Morning all,
I'm hoping someone can please point me in the right direction.
My brake's aren't great when the bus is first started and after a few hundred yard's when I brake you can hear a hiss coming from the pedal area- more clutch side I would say and definitely not near the master cylinder, it then goes away until I presume pressure has built up again and then hisses again- any ideas?
Cheers Blakie

I suspect its coming from your brake servo.

R0B wrote:I suspect its coming from your brake servo.

Yes, DEEP joy if it is

Ian

Unlikely, but, did / does your bus have cruise control? There is a vacuum dump valve fitted to the pedal assembly.
There shouldnt be any vacuum in it normally, but some bright spark may have bodged it in the past.
T

Hi All,
Thanks for the reply's!
Rob, yeh I thought it might be the servo, so I took the binnacle off and drove about listening, but definitely coming from by my feet and not up top.
Tonytech, the bus had an aftermarket cruse control fitted (never worked!!) when I bought it, so will investigate further.

Could this have anything to do with the clutch master cylinder? just seems to be coming from around the clutch pedal area, but hard to have your head down there when driving and won't hiss when the bus is stationary.
Thanks again,
Blakie

so finally got the dash out to fix a long list of bits so took the servo out to find it totally brimmed i.e. poured out as soon as I moved it (knew I should have covered the carpet!!!) with black fluid so either a master cylinder leak (never had a low reservoir issue) or the servo is sucking oil from the engine- if that's possible??? i'll trace the pipe tomorrow and see if I can find the one way valve. i'll update when its fixed.