braking

[jammyjoe]

hi, i wonder if anyone else has had this problem. i've got a nova sri and every time i brake i can hear a little blow of air from the n/s/f foot well. but the brakes work fine. i'd be greatful for any feed back.
cheers:thumb:

[Jon_nova1]

have you checked the vacuum?? the pipe that goes from the inlet manifold to the brake cylinder?

[graham kirkbride]

hi mate dont worry all my novas have done this and ive had 5 models from 1ltr to gte its a hissing noise when you press the pedal and ive never had a problem my brakes have never let me down yet

[burgo]

same here ive alwas noticed the hiss on my novas

[jammyjoe]

ok cheers thanks for your help.

[Nath]

yep same for me. happens if i pump my brakes while the car is standing

[dhdev (Oli)]

The hiss noise is the servo in action. When you apply the brakes one side of the servo diaphragm will vent to atmosphere hence the hiss, the result is that there is then only vacuum on one side of the diaphragm and it moves to increase force on the M/Cyl pushrod.:thumb:

[dhdev (Oli)]

howstuffworks.com has an excellent guide on how a servo works if anyones interested :confused: