Date: Fri, 2 May 2014 17:21:47 -0400
Reply-To: "Chris S." <szpejankowski@GMAIL.COM>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: "Chris S." <szpejankowski@GMAIL.COM>
Subject: Re: Brakes- the saga continues
In-Reply-To: <CAG+p27uBd4K1TkKUt4XjaRb5s=5hxf_mchE7kL+5Q01f8Ck0dA@mail.gmail.com>
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X2 on rear brake adjusters and handbrake.
Chris.
Wysłane z iPhone'a
Dnia May 2, 2014 o godz. 15:01 William Monk <billmonk@GMAIL.COM> napisał(a):
> The first press being soft can also mean that the rears are not adjusted
> correctly. Pull the e-brake up a click before stepping on the brakes and
> see if it goes away.
>
> Bill
> Groton,CT
>
>> On Thursday, May 1, 2014, Don Hanson <dhanson928@gmail.com> wrote:
>>
>> OK a trick I learned at the racetrack....Use different colors of fluid
>> when you bleed the brakes to be assured you've purged all the old dirty
>> contaminated fluid....I use ATE Super Blue and ATE (the normal gold colored
>> stuff) , alternating each time I change the brake fluids.....
>>
>> When you see the other color coming out of the bleed tube you can be
>> assured you have completely done the job.....but....if you are sloppy with
>> any part of the job air can sneak into the lines behind the new fluid and
>> you will again have 'soft pedal'.....
>>
>> I musta bled my brakes a few thousand times when I raced my Porsche
>> because when racing, your brakes will get you more 'passes' than hundreds
>> of horsepower....and ever the Big Red Brembo super effective hollow
>> perforated disc brakes on the Porsche were not immune to boiling the brake
>> fluid etc...
>>
>>
>>> On Thu, May 1, 2014 at 8:01 AM, Alistair Bell <albell@shaw.ca> wrote:
>>>
>>> I can't comment on compressibility of fluid with large bubbles versus
>>> micro bubbles of air, but I do know that brake fluid does , or can, have
>>> air dissolved in it.
>>> Not to be confused with bubbles, which is entrapped air.
>>>
>>> Alistair
>>>
>>>> On May 1, 2014, at 7:23 AM, Gnarlodious <gnarlodious@GMAIL.COM> wrote:
>>>>
>>>> One big advantage of the vacuum method is that microscopic bubbles
>>>> expand under vacuum, causing them to flocculate faster and rise to the
>>>> top sooner. I've noticed with pressure bleeding it can take some time
>>>> to get microscopic air out of the system. If you watch fluid through a
>>>> clear tube you see cloudy brake fluid coming out under pressure, but
>>>> that just means microscopic air bubbles are incorporated in the fluid.
>>>>
>>>> As a wild guess, I would say that one large bubble has more
>>>> compressibility than a million small bubbles totaling the same volume
>>>> of air. That would explain why your Vanagon's brakes feel fine
>>>> immediately after bleeding but a few days later they are all squishy.
>>>> This has happened to me several times and is something of a mystery.
>>>> Someone more versed in physics could dig up the facts, I nominate
>>>> Alistair Bell.
>>>>
>>>> -- Gnarlie
>>>>
>>>>
>>>>
>>>>> On Thu, May 1, 2014 at 7:38 AM, Mike B <mbucchino@charter.net> wrote:
>>>>> Regarding the brake bleeding process. It all depends on you method
>> used.
>>>>> If you use a Motive pressure bleeder, it's a simple one-man process,
>>>>> and it's hard to "do it wrong".
>>>>> If you use a vacuum hand-held, hand operated brake suction device,
>>>>> you need to grease the threads of each bleeder to prevent suction of
>> air
>>>>> through the threads, but otherwise, it's also pretty hard to "do it
>>> wrong".
>>>>> If you do it the old-fashioned 2-man way, there's a way to do it
>>>>> wrong and a way to do it right. The right way to do it is to attach
>> an
>>>>> 18" rubber hose to the bleeder and put it in a small plastic or glass
>>>>> jar with a inch or so of brake fluid in it. (you could also buy a
>> '1-man
>>>>> brake bleeder' tool, which is basically this). One guy does the pump
>>>>> and hold on the pedal, while the other guy opens the bleeder and
>> watches
>>>>> the fluid/ air squirting into the jar. Repeat on each wheel until
>>>>> there's no more bubbles, being sure to stop every so often to check
>> that
>>>>> the reservoir isn't getting too low. Use 3 sharp quick pedal strokes
>> to
>>>>> force air from all of it's hiding places, then hold until instructed
>> to
>>>>> let go by the guy manning the bleeders. Start at the farthest away
>>>>> (right rear), then move to the next farthest bleeder (left rear), then
>>>>> right front, then left front. You may need to go around them two or
>>>>> three times to get it all, and a hard pedal with no squishiness is an
>>>>> indicator that you're done. Be sure to do enough to clean all of the
>> old
>>>>> dark fluid out and replace it with fresh clear fluid.
>>>>> If you do it without the jar and hose, you will make a mess of
>>>>> spilled fluid everywhere (it eats paint!), have lots of problems (like
>>>>> Don mentions) and depending on your methods and procedures, you may
>> not
>>>>> be able to get every last bubble of air out of the system.
>>>>>
>>>>> Mike B.
>>>>>
>>>>>
>>>>>> On 5/1/2014 9:17 AM, Don Hanson wrote:
>>>>>>
>>>>>> Squshy brakes: Bleeding the system carefully should stop that.
>>>>>> "Carefully" being the operative word...Brake bleeding is intolerant
>> of
>>>>>> sloppy or slipshod work....any lapse at all during the brake bleeding
>>>>>> process can render the whole procedure a waste of time...It can be a
>>>>>> tedious job, relatively simple in concept but one that demands you
>>> make no
>>>>>> mistakes along the way...It takes a fraction of
>
>
>
> --
> Sent from Gmail Mobile
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