Date:         Mon, 17 Apr 2000 14:32:13 -0700
Reply-To:     BRENT CHRISTENSEN <bchristensen@INFOGENESIS.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         BRENT CHRISTENSEN <bchristensen@INFOGENESIS.COM>
Subject:      Re: Aaaaargh!  Brake failure (long)
Comments: To: "ehall@together.net" <ehall@together.net>
Comments: cc: stuart@COBALTGROUP.COM
Content-Type: multipart/alternative;

Thanks for all the great info.  Here are some responses...

>  The brake fade you are experiencing is due to vaporization
> of brake fluid (more
> specifically, whatever is in your brake lines, it may be a
> combination of brake
> fluid and H2O). What kind of fluid did you use? What is its
> boiling point?

I am using brand new Prestone DOT 4 fluid (FLAPS doesn't carry Castrol).  I
flushed and refilled the entire system when I did the brake job.

> mentioned the need to pump once to gain a firm pedal, that is
> a sign of air in the brake hydraulic system, how did you bleed the brakes?

> Did you flush the lines until clear?

I first used a pressure bleeder to flush the system out and do the fronts.
My wife helped me do the rears in the "traditional" manner.  "Pump it up...
Hold it... Pump it up... hold it..."  since the pressure bleeder over fills
the M/C and it is a hassle getting the excess fluid out.  BTW, I ran about 1
Qt. of new fluid through the system to flush it out.

> binding? Perhaps if air is in the system, it is staying slightly
pressurized after
> letting off the brake pedal causing brake system heating during normal
driving. Did
> you adjust the rear shoes properly so as not to bind? When driving long
> mountain passes, I

Hmm... this sounds plausible.  All this has me wondering if I really missed
something when I bled the system.  I have probably done 100 brake jobs (I
used to turn wrenches at a garage when I was in college) and I have never
had these kinds of problems.  I am suspicious of a note I saw in the Bentley
that refers to flipping a lever on the porportioning valve, and
disconnecting the vacuum line on the booster before bleeding the brakes.  Is
this important?

Brent Christensen
'89 GL Syncro Westy
Santa Barbara, CA

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