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Re: Opinions wanted on "new" clutch bleeding procedure (was Need help bleeding cutch)

You have probably finished the job by now but I can't resist. I have not
seen this posted so here it is.

For those without a pressure bleeder (and some who do) there is a simple
trick which sometimes works when nothing else will.

The brakes and clutch share a common reservoir (although segmented). Because
of this you can simply run a hose from the front brake caliper bleeder to
the slave cylinder bleeder, open both and pump the brake pedal. This forces
fluid out of the caliper through the slave cylinder and back into the
reservoir. If you pump long enough you can recirculate all the fluid (don't
now why one would). No issues of filling the reservoir until you are done
either. Start with fresh DOT 4 in the reservoir and pump some through the
caliper or you will put some (probably) dirty fluid into the clutch.

Bryan Doughty
----- Original Message -----
From: Avram Dorfman <dorfman@est.org>
To: Todd Young <tyoung@wamnet.com>; <quattro@audifans.com>
Sent: Tuesday, July 20, 1999 6:19 AM
Subject: Opinions wanted on "new" clutch bleeding procedure (was Need help
bleeding cutch)

> Well, either this will help you, or you'll tell me why not & hopefully
> my brother won't get stranded as a result...
> We may have found the perfect tool for pressure bleeding the clutch,
> because you already have one! Believe it or not, it's the clutch slave
> cylinder. (For those new to the thread, this is for an '88 80q)
> Here's what we did:
> 1) remove the slave cylinder (1 bolt, but kinda hard to get to)
> 2) open the bleeder valve
> 3) compress the slave cylinder piston (dumping fluid & air out the
> bleeder)
>     we just pressed it against the subframe, it's a pretty strong
> spring.
> 4) close the bleeder valve
> 5) let the cylinder piston expand back out (it's on a spring)
>     this causes the cylinder to suck fluid in from the reservoir
> 6) repeat from #2 until only fluid comes out
> 7) reinstall the cylinder (takes some effort b/c you have to compress it
> in an awkward position to get it in place)
> it's no surprise that the slave cylinder can create a strong enough
> vacuum to suck the fluid in.
> Now that I know how it should be done, it would probably be easy to
> reverse the procedure, putting a tube from the bleeder into a bottle of
> fluid, having the slave suck fluid in from the bottle, closing the
> bleeder, and using compressing the cylinder to push fluid through the
> system into the reservoir.
> What we did seems to have worked find though. Any thoughts?
> Todd Young wrote:
> > He-he, you need to "pressure" bleed the clutch.
> >
> > In other words, you need to force the fluid "into" the bleeder screw
> > and through the system, out into the reservoir.
> >
> > So, you will need to rig up a pressure bleeder. Basically some
> > container that will hold pressure and has an inlet for pressurized
> > air, and an outlet for the fluid. Just make sure not to empty the
> > container and force air into the system.
> >
> > I was going to bleed my clutch and brakes this weekend. I had
> > previously bought a MityVac vacuum pump with the brake bleeding
> > accessories. I figured I could just use the same container for both
> > vacuum and pressure bleeding. Doesn't work. The container won't hold
> > pressure, works fine for vacuum. So I spent Saturday evening finding
> > an appropriate container and Sunday finding fittings to make it all
> > work. Now I just need to "build" the container.
> >
> > Avram Dorfman wrote:
> >
> >>  I'm having trouble bleeding the clutch in an '88 80 quattro. Here's
> >> what happens: 1) we open the bleeder valve2) we step on the clutch3)
> >> Air & a little fluid comes out4) we close the bleeder valve5) we
> >> lift the clutch off the floor (it doesn't come up on it's own), and
> >> there's a little resistance6) we open the bleeder valve to do it
> >> again7) air gets sucked into the bleeder valve as soon as we open it
> >> it appears as though we're creating a vacuum in the line when we
> >> lift the clutch. For some reason, fluid from the reservoir is
> >> apparently not going into the line to replace what came out when we
> >> lift the clutch. Here's the background: We just put the transmission
> >> back in. We bled the clutch while it was hanging free & the trans
> >> was out, and it worked fine. Is it possible that we did something
> >> wrong when we put the slave cylinder back in? Can anyone thing of
> >> anything else that migh be causing this problem? -Avram
> >
> > --
> > -----------------------------------------------------------
> > Quote for the day:
> > Of course I don't look busy, I did it right the first time.
> > -----------------------------------------------------------
> > Todd Young              WAM!NET Inc.
> > tyoung@wamnet.com       655 Lone Oak Drive, Bldg#A
> > 651-256-5051            Eagan, MN 55121
> > 800-585-1133 ext.5051   http://www.wamnet.com/
> > '93 Audi 90S(|___\====OOOO====/___|)
> >