Re: Bleeding Brakes!!!

["Mark Battley" <m.battley@domain.elided>]

<I have recently replaced the brake boosters on my '69 1750 Spider, and I am
having
<trouble expelling all of the air from the brake system.  I have tried the
old
<fashioned way with the wife operating the brake pedal, and me on the bleed
nipple,
<and I have also tried the Mityvac single handed brake bleeding pump.  I can
draw any
<amount of brake fluid through the system, but still cannot purge all of the
air.
<What is the trick?  Any and all advice will be greatly appreciated.

You say boosters: I presume that you mean that it is a twin remote booster
system?

If so, then try bleeding it with the engine running so that the remote
boosters function properly. Unlike a conventional system that has the
booster mechanically attached to the master cylinder,  the remote boosters
rely on having vacuum to function properly. I normally bleed it once or
twice with the engine off, then start the car and do it again. I might be
imagining it, but it seems to help. Just remember to open the garage door so
the exhaust can get out!

I have had good success with speedbleeders (replacement brake bleeding
nipples with check valves built in), have a look at
http://www.speedbleeder.com. But they don't do anything that you can't do
with a willing wife..... Ahem, perhaps not, you know I mean  :-))

If you still have problems, then it is possible that there is a slight
airleak somewhere in the system that is sucking air in. I don't understand
how, but it does happen. Possible culprits include the block on the firewall
that splits the circuits, and the brake light switches (one on the firewall,
one at the rear of the car).

Good Luck!

Mark Battley
Auckland, New Zealand.

1973 Alfa Romeo 2000 GT Veloce

Alfa Romeo 105 series Bertone Coupe home page and register at:
      http://www.geocities.com/MotorCity/1806/105GTV.HTML
 

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