View single post by UKJames
 Posted: 09-14-2014 01:53 pm
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Joined: 04-24-2014
Location: Berkshire, United Kingdom
Posts: 42

Slowly working my way around the JH and have replaced calipers, flexi's, master cylinder and lines, and put in a set of green stuff pads for good measure. Brakes are now useable and progressive, but still do not bite down as much as I would have hoped. Bled the brakes thoroughly. Good pedal pressure.
So looking at my booster I've done a vacuum test, it holds vacuum. I've replaced the non-return valve, the hose to the manifold (and fitted an in-line non return valve as well).
However two things I have noticed that may or may not be related (or maybe my brakes are as good as they are going to get):

1) When I depress the brake pedal, and keep my foot down, there is a constant 'chuff chuff' sound that sound like air leaking somewhere. Diaphragm? but if the diaphragm's gone wouldn't the booster not be able to hold vacuum?

2) Manifold vacuum low- I know that long duration cams can cause this (and I believe the stock JH cams are) but surely this would affect the vacuum to the booster? My readings at idle are around 10in.

Any thoughts on this appreciated