Date:         Fri, 29 May 1998 18:05:27 -0700
Reply-To:     Tom Young <young@SHERLOCK.SIMS.BERKELEY.EDU>
Sender:       Vanagon Mailing List <Vanagon@vanagon.com>
From:         Tom Young <young@SHERLOCK.SIMS.BERKELEY.EDU>
Subject:      Re: Why do I have to pump my brakes?
Comments: To: David Marshall <vanagon@volkswagen.org>
Comments: cc: Vanagon@VANAGON.COM
In-Reply-To:  <3.0.3.32.19980529175222.00718278@mail.abccom.bc.ca>
Content-Type: TEXT/PLAIN; charset=US-ASCII

On Fri, 29 May 1998, David Marshall wrote:

> Lately my 1988 Double Cab requires me to pump my brake pedal once so it
> will grab a little better.  If I push the pedal down on the first pump it
> will go 2/3 of the way down and it will softly stop the truck.  If I pump
> it again it will only go 1/2 of the way down and I can stop much better.
> It is a bad master cylinder, bad rear brakes or what?

I would think any of the things you mention, and more, could cause this.
Definitely sounds like a leak somewhere.  I'd first pull the drums and
check for leaks in the slave cylinders; gentley skin back the rubber boot
covering the cylinder to check for non-visible leaks.  Getting at the
front brake calipers is a little harder, but I'd at least remove the
wheels and check carefully for any signs of leaks.  Look over the brake
lines and master cylinder too.  If nothing obvious pops up then I'd bleed
the the system and run it for a while to see if it remains stable.


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Tom Young               young@sherlock.SIMS.Berkeley.EDU
Lafayette, CA  94549    '81 Vanagon
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