Date: Sat, 26 Feb 2005 09:27:25 -0800
Reply-To: Alistair Bell <albell@UVIC.CA>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Alistair Bell <albell@UVIC.CA>
Subject: Re: Question about pressure bleeder
In-Reply-To: <42203B26.32269.90666C4C@swright.zuiko.sls.bc.ca>
Content-Type: text/plain; charset=US-ASCII; format=flowed
Shawn,
my version of the pressure bleeder (not as nice as the BMW chap's one)
works just fine with the pedals in the up, relaxed, position. I guess I
was "unencumbered by the thought process" for I never considered the mc
piston position.
I would suggest you run it "wet", that its the press bleeder fills the
reservoir as it goes. In my bleeder, I use a bike pump to pressurize
the system, and I run around 10 - 15 psi as you mentioned.
I was surprised when I first used my contraption for there was no mess,
lucky I suppose? I like the BMW chap's modification to the filler cap
that allows the reservoir to be left filled at the correct level.
I have to say again, using a press bleeder makes all of the hydraulic
bleeding a joy (well, you know what I mean). Just going from slave to
slave and cracking the nipple is sure a lot nicer than the "pump to
bleed" or vacuum bleeding. But this is only the case if your bleeder
constantly fills the reservoir, and if the bleeder has enough capacity
to "store" a good charge of pressurized air.
One more thing. Make your collecting vessel carefully, You don't want
it falling over and spilling fluid.
Alistair
'82 westy, diesel converted to gas in '94
http://www.members.shaw.ca/albell/
On 26-Feb-05, at 9:02 AM, Shawn Wright wrote:
> I'm planning to build a pressure bleeder to hopefully resurrect my
> clutch.
> I've read numerous posts and web articles on these things, including
> both
> a wet and dry approach (pumping fluid or just air). I'll probably try
> the dry
> approach first to reduce possible mess.
>
> My question is this - one article mentions that you're forcing fluid
> past the
> master cylinder seals, which is something I had been wondering about.
> Isn't there position in the piston stroke where fluid is allowed to
> enter the
> cylinder? I imagine there must be, and if so, what is this position?
> It would
> seem the resting positon would be the only way it could work. So
> doesn't
> this mean the pressure bleeding doesn't actually force fluid past the
> seals
> as long as the pedals remain in the up position?
>
> Also, the same article mentions clamping the hose leading to clutch
> master
> cylinder (not a Vanagon, but similar I guess) to avoid leaking at this
> hose,
> since it's not designed for pressure. I'm thinking of trying 10-15 psi
> at most
> and watching carefully for leaks. Any other tricks or tips?
>
> Thanks.Shawn Wright
> http://zuiko.sls.bc.ca/~swright
> '85 Jetta TD (retired)
> '85 Jetta D
> '88 Westy 2.1L
> '82 Diesel Westy
>
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