Date: Tue, 23 Mar 2004 23:24:51 -0600
Reply-To: Paul & Becky Oliver <oliver8@TDS.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Paul & Becky Oliver <oliver8@TDS.NET>
Subject: Re: Very soft brake pedal unless it is pumped?
Content-Type: text/plain; charset="iso-8859-1"
I'll have to think on it some more but when master cylinder's go bad they
have a few other signs. Generally the pedal will go to the floor, it maybe
very slow but they will eventually get there.
You may have to press on it so hard you'd think you were going to break it
off or bend it. Then there should be traces of brake fluid leaking or
dripping from the master cylinder. Pull the vacuum booster hose/line and you
should find some fluid in the line. If none of these other things are
present and you pedal does not go to the floor no matter how hard you press
on it, the master should be fine.
Look at all joints, fittings and wheel cylinders for signs of fluid, you may
have a loose fitting that will allow a small fluid leak but air will be
drawn back into the system when pedal is released. And it is possible to
have a leak so small that it will not let fluid out but will let air in. An
air molecule is much smaller than that of the oil/fluid and does not have
the surface tension that all fluids have.
Re-torque all your bleeders, they may not be closed tight enough, or there
maybe a small piece of dirt that has kept them from seating properly. Loosen
them let a small amount of fluid out and then re-torque.
To check them for leaks, use a small hose (very tight fit over bleeder) and
place into a clear bottle with "graduation markings" (or make lines on it or
tape, etc). Jar must sit still and level mark fluid (water line) work brake
pedal several times. Review jar to see if the level has moved down any.
You might just take some silicone and force a small amount into the hole in
the bleeder which should seal off any air that might try to enter. If the
problem goes away, then you were "back feeding air" into the system.
Paul
----- Original Message -----
From: "Joy Hecht" <jhecht@ALUM.MIT.EDU>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Tuesday, March 23, 2004 8:26 PM
Subject: Re: Very soft brake pedal unless it is pumped?
> Given my general level of knowledge of auto mechanics, I hesitate to reply
> to this - but as no one else has... Back before my Honda Civic got stolen
> my brake pedal went soft in that way. Had to replace the master cylinder.
> So perhaps that could be it on your van, if you've bled the brakes.
>
>
> Joy
>
> > -----Original Message-----
> > From: Vanagon Mailing List [mailto:vanagon@GERRY.VANAGON.COM]On Behalf
> > Of Kurt Camealy
> > Sent: Tuesday, March 23, 2004 1:54 PM
> > To: vanagon@GERRY.VANAGON.COM
> > Subject: Re: Very soft brake pedal unless it is pumped?
> >
> >
> > Well I bled the brakes as advised and the problem went away. At least
> > for a few days... Now the pedal is slowly getting softer each day.
> > Again I can pump it twice and it firms right back up. The pedal also
> > doesn't keep falling once it reaches its firm point if I hold it down.
> > I am assuming air is entering my system somewhere. The only problems I
> > had when doing the work below was a slightly leaking rear drum cylinder
> > if the piston comes out too far and I also accidentally dropped one of
> > the front calipers and it stopped hard hanging by the flex line.
> > However over these few days I have checking that front line and there is
> > no fluid leakage and the reservoir has not dropped at all.
> >
> > Any ideas?
> >
> > Kurt
> > 87 Wolfsburg GL
> >
> > -----Original Message-----
> > From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf
> > Of Kurt Camealy
> > Sent: Friday, March 19, 2004 1:27 AM
> > To: vanagon@GERRY.VANAGON.COM
> > Subject: Very soft brake pedal unless it is pumped?
> >
> > I just replaced my front bearings (requiring removal of the calipers)
> > and my rear brake shoes. When I went to test drive the car the pedal
> > went almost to the floor and then slowly stopped the van. I followed
> > the Bentley exactly on the rear drum adjustment. I even tightened the
> > adjusters until there was drag on the drums then backed off a couple
> > clicks. The emergency brake works great as well. The system was never
> > opened in the front or rear so what is going on? If I pump the pedal
> > the travel is greatly reduced and it firms up to stop the vehicle. It
> > also doesn't appear to sink after pumping until the next time I go to
> > brake. I am leaving for a trip tomorrow and have no clue what is going
> > on?
> >
> >
> >
> > HELP!
> >
> >
> >
> > Kurt
> >
> > 97 Wolfsburg GL
> >
