Date: Wed, 8 Jul 2009 18:02:29 -0700
Reply-To: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: Scott Daniel - Turbovans <scottdaniel@TURBOVANS.COM>
Subject: Re: here's a trick you seldom get to use ......bleeding clutch
slave
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yes, is the short answer.
the 'check valve' is the ole 'clear tube stuck into a jar of brake fluid/.
You use a clear tube so you can see bubbles as the come out of the system,
and also so you can tell when 'old-yucky' is turning to 'new fresh' , and
it's time to move on to the next wheel.
When you let the brake pedal return to the up position ..........the old
brake fluid can't flow backwards back up into the brake system, with this
tube in a jar method. The bottom of the tube needs to be well below the
surface of the brake fluid in the jar of course.
the other low tech 'pedal method' takes two people ............one to
operate the brake pedal and keep the res full ......
and the other to open and close the valve.
you know..........the ole .............
'valve open, push pedal down, close valve.'
let pedal back up, ( pause with pedal up so fluid from the res can enter the
chambers where pressure is developed in the mc ) .....
repeat.
Called 'the two person method.'
the first one ........
that's called the 'Single Person, tube in a jar method.'
as I mentioned recently, it's important to not stroke the brake pedal on a
used master cylinder all the way to the floor. Doing so will cause the seals
to rub over areas in the mc they normally never touch, would could be rough
or corroded...........and thus harm the seals. So half stokes only.
Pedal stroking speed..................is very important.
'about medium speed.'
too fast foams things up.
too slow is tedious and just doesn't feel right. 'medium speed, half
strokes only, pause at the top of the pedal stroke."
Trivia/errata :
What is the only vehicle ( there *must* be others though ! ) ........that
you can check the brake fluid reservoir level on while driving down the road
?
and what is the only vehicle ( there must be a few others though ) where you
can bench bleed a new master cylinder in the car or van. , after it's
mounted in the
car or van ................by yourself ??
Name a vehicle that uses an engine oil drain plug that works like a bleed
valve.......
you just unseat it to make the oil drain, no need to remove it completely ?
( though it's not hollow like a bleed valve is , .but it unseats from a
tapered seat, like a bleed valve does ) .........it's in 'our family'
here of vehicles we appreciate , not some off the wall thing .
btw............working on and driving many vanagons ..........
I can tell how deteriorated the brake fluid is ......by how the brake pedal
feels. Nice thick new brake fluid (say a year old or less ) feels a lot
nicer than 5 year old, semi-water brake fluid, I must say !
and clutch hydraulics ................they need bleeding just like brakes.
Amazing how thick clear brake fluid can turn to thin dark water after a few
years.
its' so fun to take care of them !
----- Original Message -----
From: "pdooley" <psdooley@VERIZON.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Wednesday, July 08, 2009 2:39 PM
Subject: Re: here's a trick you seldom get to use ......bleeding clutch
slave
> The pressure bleeding via brake system is an interesting idea, but how do
> you keep the fluid flowing? Wouldn't you need some sort of check valve to
> keep the fluid from pulling back to the MC as you pump the pedal?
>
>
> -----Original Message-----
> From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of
> Mike
> Sent: Wednesday, July 08, 2009 4:48 PM
> To: vanagon@GERRY.VANAGON.COM
> Subject: Re: here's a trick you seldom get to use ......bleeding clutch
> slave
>
> Ditto, Don and Scott!
>
> But, I may never get to use it; I have both a Motive unit and and auto
> transmission.
>
> I wonder, if you get a long enough hose, could a person bleed a different
> vehicle's brake/ clutch systems (using the good vehicle's brake system for
> pressure)?
> Hmmmm, we may haved stumbled onto something here. It seems to me to be a
> 'poor man's' version of a power-bleeder!
> I volunteer Scott to give it a try, and report back to us
> all.............
> Mike B.
> Neat trick.
>
> Power bleeding with a Motive Power bleeder is the better way than a
> Vacuum
> Bleeder...
> When you are alone, the pressure-style bleeding systems are pretty
> fool-proof. I used to sometimes bleed brakes a couple of times per day
> in
> my racecar..So I do have some experience with that stuff.
> Don Hanson
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