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Brake bleeder

Dan wrote:

Perhaps we can summarize the procedure for building a brake bleeder
once and for all?  I've seen the metal cap at www.ultimategarage.com,
but a free spare brake fluid reservoir cap beats $30 for a metal
one.  I got a boltin tire valve (Camel) for $1.50 at Pep Boys,
and I think that's all I need - set compressor to 20psi, drain and
refill reservoir with clean fluid, pressurize and bleed.  Right?

No, Dan, 5 to 10 psi max! You may blow out the O-rings and seals in your
brake system if you apply too much pressure.

Even at 10 psi you will pop that plastic reservoir cap off the reservoir
and have a geyser of brake fluid all over your car. BTDT.
Fortunately I have a habit of covering both fenders with lotsa terry
towels AND having a bucketful of water on hand whenever I bleed the
brakes. When the plastic cap popped I just flooded the whole engine bay
with water. It saved the paint.

I machined an Al ring and knurled it on the outside. After which I press
fitted it over the OEM plastic cap with some Armstrong A-12 epoxy just
to make sure that the ring holds the cap tight. Works well so far. The
Al ring prevents the plastic cap of expanding under pressure and popping
off the threads on the reservoir's neck.

If you don't have the machining facilities at work I suggest that you do
buy that $30 metal cap just to be safe.

You also need a transparent intermediate container made out of glass (or
poly carbonate if you don't use ATE Super Blue brake fluid coz this
aggressive blue $hit eats through poly carbonate in a few minutes after
which the container goes KABOOM! under pressure and splatters brake
fluid all over the engine bay. BTDT).

This container should also have the tire valve stem in the cap for
applying pressure to the surface of the brake fluid. It also should have
a pickup tube that goes to the very bottom. The top end of this tube
should have a clear braided Tygon hose attached to it. Attach a quick
tire valve stem disconnecting clamp to the opposite end of the Tygon
hose in order to connect it to the tire valve stem in the brake MC
reservoir cap.

I use an empty freon tank as an air source. I brazed a "T" to it's 
valve and attached a pressure gauge and a pressure setting valve. Both
are a must-have on the brake bleeder, whatever the air source you are

Igor Kessel
'89 200TQ -- 18psi (TAP)
'98 A4TQ -- nothing to declare
Philadelphia, PA