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Subject:Re: Air in Brake Circuit
From:Mark Hudgik
Date:Mon, 15 Dec 1997 17:26:09 -0500

Mike,

In addition to checking the reservior connections the only other thing I can
think of is the bleeder itself. I have seen cases where it had been over-torqued
previously, scoring or distorting the bleeder valve seat. Turning it in by hand
between pedal strokes was not enough to completely close it, allowing air back
in on the pedal upstroke.

Snugging down the bleeder with a wrench between pedal strokes will sometimes
overcome this. Or if you're already doing this, you could try a new bleeder
screw.

The hand vacuum pump method gets around this type of problem because it has a
built-in check valve and doesn't allow air back into the system. Then all you
have to do is figure out why you keep getting brake fluid all over the ground
later on.  ;-)

Hopefully some of this helps ....
    - Mark

Michael A. Radtke wrote:

> 3) Air leak.  I have no doubt that there is an air leak.  The problem is
>    that I can't figure out just where.
>
>    I will wet the reservoir connections with brake fluid to see if the leak
>    is there.
>
>    Any other air leak that I have has to act like a check valve.  I have no
>    fluid leaks.  Yet the front system is full of air.  Perhaps another
>    clue.  If I pump the pedal a few times and then release it, I definitely
>    can hear sound from the master cylinder of air squirting around in
>    fluid.