John,
Don't rule out a problem in the MC ... there is a little valve with
a small rubber seal that seals the circuit to the reservoir when you apply
the brakes. If that seal's shot you'll get exactly those symptoms. Have
someone apply the brakes while you watch the level in the reservoir ...
if the fluid level rises when you apply the brakes then this is your problem.
If you're losing fluid from the reservoir, however, it's probably getting past
the "gland seal" in the booster (assuming the PBR servo is similar to the
stock Girling).
bs
********************************************
Bob Spidell San Jose, CA bspidell@pacbell.net
'67 Austin-Healey 3000 '56 Austin-Healey 100M
********************************************
> After several years of driving my 65 BJ8 without a
> brake servo, I finally got around to rebuilding
> (replacing all seals in) my PBR unit. The main
> cylinder looked excellent without any noticeable
> scratches or scoring, hence I did not have it
> resleeved.
> After reinstalling the unit, I bled it, then proceeded
> to bleed all four wheels. When I step on the brake
> pedal it goes right to the floor with no resistance
> whatsoever. However, if I pump it rapidly with about
> a half a dozen strokes, it builds up pressure to what
> I would consider about the right amount of "pedal".
> It has a somewhat cushioned feel, as I would expect
> with a servo. (previously a very firm pedal without
> the servo). If I hold it there, it doesn't seem to
> fade as long as I don't completely release the pedal.
> But as soon as I let it return completely to it's
> fully released position, I lose ALL pressure, and it
> now goes right to the floor again! The master cylinder
> was working fine before introducing the servo????
> Any suggstons would be greatly appreciated.
> Thanks, in advance,
> John Lakie
> 65 BJ8
> Ontario, Canada
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