Hello all,
By now I truly had hopes of sharing my story with a total brake replacement
on my 1980 Spitfire. The whole story will follow completion of the work,
but I really could use some advice. It has been a long time since I did a
total brake job (1974 Vega Kammback...), but this has turned into a major
re-education and nightmare. The car has been on stands for a month now in
total.
Problem: Brake system stubborn when trying to bleed it. Little to no
fluid coming down the lines from the Master Cylinder. Air bubbles never
cease. Using a Mityvac unit. Lines were cleaned with brake cleaner (good
old TCE), blown air dried, sat 1 week prior to reassembly. All metal lines
reused with exception of right rear. Pressure Warning Switch reused (did
not disassemble, as there was no problem with it prior to brake work).
Replaced to date:
Front:
Master Cylinder (professionally rebuilt, reuse of original reservoir),
flexible brake lines (Aeroquip braided installed), professionally rebuilt
calipers, new rotors, new pads).
Rear:
New drums, pads, all new hardware, new Aeroquip flexible lines, new wheel
cylinders. Right rear metal line at wheel replaced due to stripped fitting.
Brake system had a problem with the master cylinder, where it would
spontaneously lose pressure without predictability. You could be sitting
at a stop holding the car with the brakes, then the pedal would suddenly
drift to the floor.
Now that the system is reassembled, I cannot seem to get any fluid to come
out of the left front caliper after pumping the system with the Mityvac. I
did bench bleed the master with the DOT5 fluid, and then did it again with
the Mityvac.
Pumping the right front and the left rear did finally result in some fluid
filling the Mityvac reservoir. I kept at it for a good 15 minutes of
continuous suction with the Mityvac, and still I kept getting mainly air.
I heard a rumor that you are supposed to use some sort of special grease on
the fittings when attaching the braided Aeroquip lines to the stock pipe
fittings. Is this true? I doublechecked the fittings and they are as
tight as they can go without stripping fittings or snapping lines.
The line from the Mityvac is sealing tightly on the bleed nipples. It does
not appear that there is a airleak there. Could enough air leak in from
the loosened bleed nipples to still cause air to bubble into the pump,
making it appear like there is still air in the system?
Would it be possible that the Pressure Warning Switch is a problem and may
be jammed (wonderful reputation there, and harder to find a
replacement)? How can I isolate the problem to the switch (I can't replace
every little part I touch, though it seems that way of late).
I do hope that someone has the magic answer. Also, if someone knows where
I can get a replacement electrical connection for the Pressure Warning
Switch (normally part of the harness), I would be greatful. One of the
connections seems to be pushed out of service and it does not seem to be
repairable. Can't identify availability of this little rubber boot
connection in the Vicky Brit catalog, nor the Roadster Factory catalog.
Cheers,
Ron Deaver
Issaquah, WA
1980 Spitfire 1500 (yet to be named)
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