Dear Listers,
Over the past few weeks I have:
1 - rebuilt calipers
2 - turned discs
3 - replaced rear flex hose
4 - removed pressure-reducing valve
5 - checked master cylinder function
6 - attempted to check pressure-reducing valve function
7 - removed and un-blocked steel line from pressure-reducing valve to rear
circuit
8 - replaced steel line from rear flex-hose to right rear wheel cylinder (twice)
9 - replaced steel line from right rear wheel cylinder to left rear wheel
cylinder (twice)
10- replaced right rear wheel cylinder
Items 8 & 9 were initially replaced with 2nd-hand parts, from a parts-TR7 in
storage. When the unions still leaked, I blocked off the rear circuit (with
a bleeder screw in the outlet port of the right-rear wheel cylinder) and
drove to a brake shop. He found the unions stripped, and the flared tube
ends incapable of sealing. Moral: don't buy used brake lines!
Now, the car much worse than it did with a leaking caliper and a blocked
rear circuit; the feels mushy, and has excessive travel. I guess the master
cylinder had seen all it's mates getting rebuilt or replaced, and decided to
join the fun.
My mate and I were pretty aggressive when we tried to bleed the rear
circuit. He would pump ten times, hold it down hard, then I'd open bleeder
for a few seconds, and air would gush out. Being gentle achived no movement
of air or fluid whatsoever. (I also had an Eezy-Bleed supplying about 20 PSI
to the master, during the operation.)
So, has anyone known a master cylinder to pack it in after a heavy bleeding
session? (It is a rebuilt, sleeved unit with about 4 years' service, and
about 4 years of disuse.) Should a TR7 be _this_ difficult to bleed? (NB:
The fronts were a piece of cake.)
To say that I'm reaching the limit of my patience would be like saying
H-bombs are loud. I must have run over Henry Ford's granny in a former life!
Allen Nugent
Graduate School of Biomedical Engineering
University of New South Wales
Sydney 2052 Australia
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