Peter: I cant believe no one had mentioned this to you yet, but you
have to also bleed the booster. Have you done this?? Once the brakes
are bled(and between you and me, I agree that buying brake bleeding
devices is unneccessary) you need to also bleed the booster, the
bleeder screw is the same as on the brakes. Hopefully that helps you.
I dont see the point in buying brake bleeding equipment for a job that
is easily done using two people, if you have the people power, its
just as quick to pump pump pump hold and crack the screw. I do have a
bleeding device as my girlfriend is sometimes unwilling and/or
unavailable, but you dont really need one. IMHO.

J

On 18 May 2004 09:27:47 -0700, xstreamcanadian (AT) hotmail (DOT) com (John) wrote:

Just be sure the pumper does not bottom out the piston in the MC bore. That can
ruin the seals and put you in the market for a enw MC.

I've done bleeding a lot of different ways. Usually I use gravity bleeding. I
just bought a vacuum bleeder, which I think is the best of all possible choices.

- Easiest on the hardware
- Does not force air into the fluid like a pressure bleeder (the pro versions
have a rubber bladder to prevent this)

Don't need a girlfriend, or a bleeding device?
[avoiding the obvious opening]
Texas Parts Guy

John wrote:
Could you elaborate on this? I replaced the MC on an '87 GTi and I can
assure you that the booster was not in any way connected to the
hydraulic system. What am I missing here?

You are missing nothing. The vacuum booster runs on air or lack of it.
Nothing to bleed. You start the car and it vacuums out properly. I
think someone has used some terms incorrectly.

Randolph <trash (AT) junkmail (DOT) com> wrote:


Jim B.

I straightened my rookie cap today and started over trying to do
everything very carefully. I'm a lot closer but still not there.
From replacing the rear pads a few years ago I think I remember that
when everything is bled and all the boost is gone, the pedal stops
after only about 1/4 of full travel. Right now I'm getting it to stop
about 1/2 or 2/3 of the way down after 3 pumps, first pump still goes
nearly to the floor; I've bled many quarts of fluid through the
system. The DOT4 stuff the reservoir says I should use is hard to
find for some reason as well. Everyone's always out of it. I've
cleaned out three stores now.

I did have the parts to bench bleed the master cyl so I did that. I
also noticed that the reservoir does not snap down flush against the
seals in the reman m/c like it did the original. But I don't think it
seals on the bottom face of the reservoir, rather on the two barbs, so
that shouldn't matter.

I bled all the lines again, taking out 12-16 oz of fluid per wheel the
first time around. The pedal at this point was still going all the
way to the floor. Then I released the rear brake pressure regulator,
after which it built up pressure more easily. I went around and bled
everything again for almost as long and got some more bubbles out the
back.

After all this, when bleeding, we noticed that after the 3 pumps and
opening the valve, the pedal sinks when the rr or lf caliper is bled,
but not when the others are bled, even though there's always pressure
and fluid always comes out. I guess this is telling me that there's
still some kind of big bubble in either the lr or rf line or their
common m/c section? Maybe I ruined my good work with the bench
bleeding tilting it in or installing the lines. FWIW the lr caliper
isn't clamping much without 4 or 5 pumps. The rr seems to work.

Also, the pedal still sometimes catches on the way up, with the sound
of something sucking or squirting up front. Don't know what this
could be. Don't like it.

Final scary thing, sometimes when pumping the pedal will get very
stiff after the few pumps, but then with a sound the pedal will
suddenly sink most of the way down. Scary because I imagine that
could be the stupid m/c leaking again, but in a different way than the
sinking pedal from before the replacement, and I'm looking for a high
level of confidence in my brakes. Maybe this could also be a bubble
phenomenon. Once again, I don't want to start over.

I think it's driveable now; I'm real close to throwing in the towel
and calling in the pros. I'm testing the patience of my assistant for
sure!

Thanks all, Peter.

jimbehning (AT) doesthisblockporkmindspring (DOT) com wrote in message news:<1kvka0h372kvh0s4son6cf9bibh6jio04q (AT) 4ax (DOT) com>...

I have seen some NEW brake masters that were bad, although they were for a T3.

I probably would exchange that brake master for another one. Was it new or
remanned?
I prefer good brands that are new like ATE.

When you bleed just leave that proportioning valve alone, but make sure the
lever moves freely.
Also with care you could isolate each wheel caliper by carefully clamping the
hoses closed to find out if the calipers or the master are creating your low
pedal problem.
Hoses might swell when the pedal is depressed, or those air gaps between the
pads and rotors.
Of course I am assuming that you would see any brake fluid leaks coming out of
the lines. ;-)

later,
dave
Reminder........
Before you criticize someone, you should walk a mile in their shoes. That way,
when you criticize them, you are a mile away from them, and you have their
shoes. Frieda Norris

I been watching your issue and the only suggestion I have is "are you sure
you put things together correctly"?. I have never seen a master cylinder go
bad from all the fluid draining out overnight. If you have no air coming out
when bleeding then I would look to see if the pads float freely within the
calipers, and there is no space between the pad and rotor. Are the bleeders
on top of the calipers? Sounds dumb but I have seen calipers installed on
the wrong side of the car. Hard to do in the rear but easy with the fronts.
But... sounds like you need someone else to check it out.


"Peter Stokes" <peter_stokes (AT) yahoo (DOT) com> wrote

What would be the advantage of switching to A3 calipers?
Texas Parts Guy

"Rex B" <NOSPAMrex (AT) REMOVEtxol (DOT) net> wrote

Don't quote me, but I believe they are larger. The thing is you can get
most aftermarket kits cheaper than the real A3's, and most of them are
better than stock.

I saw on a show where they hopped up a car. They installed larger
brakes on the car. They looked cool and stopped the car about 10 feet
less. Not the best investment of $1,000 I would think. Maybe with
wider tires there would be more value.

"Biz" <biznospam (AT) att (DOT) net> wrote:


Jim B.