Date: Mon, 19 Jun 2000 09:12:15 -0700
Reply-To: Tobin Copley <tobin.copley@ubc.ca>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Tobin Copley <tobin.copley@ubc.ca>
Subject: Re: Bleeding clutch system--update
In-Reply-To: <v04220804b573036eac83@[207.23.94.174]>
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At 4:11 PM -0700 6/18/00, Tobin Copley wrote:
>...new master cylinder back in without
>problems. Sean's instructions say to bleed the master cylinder at
>the hydraulic fitting until no more air bubbles come out.
>
>I've been doing this for over two hours now, and while it's pretty
>hard to distinguish air bubbles from squirts of fluid, I strongly
>suspect I still have air trapped in the cylinder. Pedal feels very
>light, and will not return without pulling back up by hand.
>Resistance is not even through the stroke--seems to have little
>resistance at top half of stroke, that a noticeable abrupt increase
>in resistance for the bottom third or so.
Thanks to all the many people who responded earlier. A few more data points:
The clutch will not return to the "up" position from the floor
without pulling it back by hand. The clutch return spring is in
place and unbroken.
I do not have a pressure bleeder. I am cracking the nut the the
hydraulic fitting at the bottom of the master cylinder, depressing
the pedal, tightening the nut, then pulling the pedal back up and
repeating the process. It feels like the pedal is not really moving
much fluid/air out--it feels kinda, I don't know, "empty."
The reservoir has plenty of fluid in it, and hardly seems to draw down.
I strongly suspect I have air in the master cylinder. Perhaps I'm
stuck in a cycle here? Perhaps I can't get a good pump of fluid at
the cylinder because of all the air in it, but can't get the air out
since I can't get a good pump?
I notice also that the hydraulic fitting is at the bottom, and air
bubbles should rise within the cylinder, right? How can i get air
trapped at the top of the cylinder out? The intake tube from the
reservoir doesn't come in from the top, so am I hooped with a big air
bubbble stuck up high in the top of the cylinder? My local mechanic
(who'd booked up for over a week) suggested pulling the MC again,
pre-filling it with fluid (upside down, perhaps), reinstalling it
pre-filled. Quickly, I suppose, since fluid *should be flowing
through it until the lower hydraulic line is connected, which is
always a bear to get the threads started on.
I few other people suggested trying a gravity bleed, and while that
certainly sounds attractive, I'm not sure it would do anything to
help clear that an air bubble stuck at the top of the MC.
And I'm on a tight dealine for a big workshop I'm giving tomorrow,
and Christa needs the car tomorrow to go into town! Aaaargh!
Right now, if I the island mechanic had space to fit me in, or the
tow truck could fit me in to take the bus to an off-island mechanic,
I'd do it since I've just got too many demands on my time right now
to risk spending another futile few hours on this thing. But the
mechanic and tow truck can't, so c'est la guerre!
Pulling my remaining hair out on Bowen island,
T.
(oh, and my transmission is making "marble-like", "tumbling gravel"
noises. I suspect this is a Bad Noise? Anybody got a good DM tranny
lying around?)
-------------------------------------------------------------------------
Tobin Copley Bowen Island, BC, Canada tobin.copley@ubc.ca
'82 westy 1.6L NA diesel ("Stinky")
'97 son Russell =============
'99 daughter Margaret /_| |__| |__|:| clatter
1995: 'Round US, Mexico, Canada 15,000 mi O|. .| clatter!
1996: Vancouver to Inuvik, NWT 7,400 km ~-()-==----()-~
Previous buses: '76 westy deluxe (Daisy), '76 westy standard (Mango)
http://www.sfu.ca/~tcopley/vw/