Re: Bleeding Brakes Procedure Check

[ti@amb.org (Ti Kan)]

Alexander van Gerbig writes:
>     When I bled the brakes on my 80 I did the following:  Jack the car up
> one wheel at a time, start the car, pump the brakes a couple of times,
> loosen bleeder, fluid flows through clear plastic tube into bottle, leave
> the bleeder open and pump the pedal moving more fluid out, close bleeder,
> pump some more, open bleeder and pump again until clean fluid comes through
> clearhose.
>     I drain the resevoir by doing that procedure until there is only 1-2
> pumps left in the resevoir, fill with fresh stuff, then bleed as described
> above all around the car.  This right, I just want to everything right when
> getting the Super Blue in?
>     Or is it better to just open the bleeder and wait for the fluid to move
> on it's own?

Bleeding the brakes is a two-person job unless you have one of those
self-bleeder devices.

These are procedures for non-ABS cars.

Start from the wheel farthest from the master cylinder and work toward
it, one wheel at a time.  You don't need to have the engine running
for this.  Have helper sit in car, while you work on the bleeder valve
at the caliper.  Connect a clear plastic hose to the valve and let the
other end immerse in a glass jar pre-filled with a little brake fluid,
so you can see the air bubbles come out.

Tell the helper to pump the brake pedal about 10 times, then hold the
pedal down.  At this time you loosen the bleeder valve and let the
fluid out.  Watch for bubbles in the jar.  The helper will note that
the pedal now sinks to the floor.  Close the valve and then tell the
helper to let up on the pedal.  Repeat the whole process a few times.
Fill the fluid reservoir with fresh fluid so it doesn't run dry.  At
no time should the helper let up on the brake pedal while the bleeder
valve is open, that would suck air back into the system.

If you don't see any more air bubbles going into the jar while the
bleeder is open, only fluid, then you are done with that wheel.

Change to a different wheel and repeat the whole things again, until
all four wheels are done.  At this point the pedal should be hard
when pressed and not feel spongy.  If it still feels soft, then you
should repeat all 4 wheels again.

-Ti
96 A4 2.8 quattro
84 5000S 2.1 turbo
80 4000 2.0
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