Date: Sun, 29 May 2011 15:21:43 -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: Brakes problems
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re
Just seemed worth the effort to give the old one a shot."
Totally reasonable to try to get some more service out of a not-dead-yet
part.
Though with a brake MC ...
it's a pretty critical part.
and look what you learned now ..
you're better at changing an MC, and you know not to stroke a used one all
the way to the floor.
Well worth the time spent.
two other tips ..
I like a tiny dab of grease on the end of the push rod that sticks into the
MC to operate it ..don't want metal to metal contact there.
and be sure the o-ring is in place at the front end of the MC where it
bolts onto the booster.
you can check down inside the booster for any old brake fluid too.
there shouldn't be any really.
Scott
www.turbovans.com
----- Original Message -----
From: "John Jensen" <bluesbug@VERIZON.NET>
To: <vanagon@GERRY.VANAGON.COM>
Sent: Sunday, May 29, 2011 1:39 PM
Subject: Re: Brakes problems
> That's all enough information to convince me to go ahead and order a new
> MC.
> Yes...I did stroke all the way. The good news is I have all new clean
> brake fluid in my
> system now. I'll be happy to hear any more opinions, if any one has some.
> I'd have probably gone ahead and gotten a new MC if it hadn't been the
> holidays.
> Just seemed worth the effort to give the old one a shot.
> Best wishes and thanks.
> '80 Westy Aircooled
>
> John Jensen
> johnjensen@johnjensenartist.com
> http://www.johnjensenartist.com
> bluesbug@verizon.net
>
>
> On 5/29/2011 3:54 PM, Scott Daniel - Turbovans wrote:
>> sure sounds like a 'new' bad used master cylinder.
>>
>> the poor things seldom get serviced anyway - like lots of old vans have
>> 'black water' in the brake system that once was nice brake fluid. ( as
>> you
>> know...bf absorbs moisture from the air ..
>> even just sitting ........eventually it turns to 'just very black water'
>> ..........and water leads to corrosion. )
>>
>> AND..........I'll bet you right here and now ..
>> tell me you *didn't* do this .. !
>> you stroked the pedal all the way to the floor in your manual bleeding
>> process.
>>
>> In case you did .........
>> One should never stoke the brake pedal all the way to the floor in
>> bleeding
>> unless it's a brand new cylinder.
>> Because ......on an old one, or a used in-service one...since the piston
>> never slides down to the bottom in normal use....there's a section of the
>> cylinder that gets rough .......from corrosion ..and from the seals not
>> sliding over that section, since the brake pedal should never go to the
>> floor anyway.
>> As soon as you stoke the pedal to the floor on a used MC ...you make the
>> seals slide over that untouched area, and that isn't good for the piston
>> seals.
>>
>> I have lots of used brake master cylinders.
>> If one works properly after being put on a van ..I consider that just
>> good
>> luck.
>>
>> And never ever stoke a used brake master cylinder all the way to the
>> floor
>> with a manual brake bleeding process.
>> ( which I prefer btw, since there's 'feel' involved in the process,
>> and you
>> can feel that it's actually producing pressure. With a pressure
>> bleeder you
>> don't get that advantage. )
>>
>> Scott
>> www.turbovans.com
>>
>>