Still bleeding the bloody brakes

[patrick flowers]

>
> I am making some progress. But still getting some tiny bubbles out. I
> initially have a firm pedal but then it will slowly sink to the floor and the
> brake light will come on.

That sounds like leak or a bad master cylinder.

> I found something interesting on the web. I'd try it but don't have time to
> wait for it to come in the mail. I'm trying to leave on a trip which I have
> already delayed.
>
> Look at this: Welcome to
> Speed Bleeder
> http://www.speedbleeder.com/
>
> Looks interesting.

I thought about speedbleeders too. Like I said the other week - once I
got close, the old "pump the pedal and bleed" technique got the pedal
up. Speedbleeders would speed this process up.

Patrick

- --
Patrick Flowers
Mailtoatrick

The GMC Motorhome Page
http://www.gmcmotorhome.com

 

[homebase1]

Theory time........
New brakes were installed and bleeding was required. The inner
bore of the master cylinder had built up a 'film' of crap over the
years. Repeated scraping of the master cylinder rubbers over this
layer of crud disturbed(groved)(wore) the outer edge of the rubber
as the peddle repeatedly pushed the piston to places where it had
not gone in years.
This type of thing frequently happens after a clutch change in some
British 'stuff' . The clutch cylinder and slave inner rubbers get
moved into un-visited territory and as a result get groved and will
not hold pressure. This realization usually occurs after 2 hrs of
bleeding and a 1/2 lb of gear metal is removed from first and/or
reverse

Mike B...slow to catch on in Nova Scotia

>
> > I
> > initially have a firm pedal but then it will slowly sink to the floor and
> > the
> > brake light will come on.
>
> Emery,
> That is a classic symptom of a bad master cylinder. Typically, it's worse
> if you press very slowly and gently on the pedal, but seals up partially if
> you hit the pedal hard. Regardless, if the pedal is firm, and slowly sinks
> (assuming you got good fluid flow from all 6 wheels when bleeding), it must
> be leaking somewhere. If not to the outside world, it must be leaking inside
> the master cylinder.
> HTH.
>
> Rick Staples
> '75 Eleganza
> Louisville, CO
>

 

[homebase1]

Geez
Think I'd better head back to the think tank !
>
Mikeb

> Theory time........
> New brakes were installed and bleeding was required. The inner
> bore of the master cylinder had built up a 'film' of crap over the
> years. Repeated scraping of the master cylinder rubbers over this
> layer of crud disturbed(groved)(wore) the outer edge of the rubber
> as the peddle repeatedly pushed the piston to places where it had
> not gone in years.
> This type of thing frequently happens after a clutch change in some
> British 'stuff' . The clutch cylinder and slave inner rubbers get
> moved into un-visited territory and as a result get groved and will
> not hold pressure. This realization usually occurs after 2 hrs of
> bleeding and a 1/2 lb of gear metal is removed from first and/or
> reverse
>
> Mike B...slow to catch on in Nova Scotia
>

> >
> > > I
> > > initially have a firm pedal but then it will slowly sink to the floor and
> > > the
> > > brake light will come on.
> >
> > Emery,
> > That is a classic symptom of a bad master cylinder. Typically, it's worse
> > if you press very slowly and gently on the pedal, but seals up partially if
> > you hit the pedal hard. Regardless, if the pedal is firm, and slowly sinks
> > (assuming you got good fluid flow from all 6 wheels when bleeding), it must
> > be leaking somewhere. If not to the outside world, it must be leaking inside
> > the master cylinder.
> > HTH.
> >
> > Rick Staples
> > '75 Eleganza
> > Louisville, CO
> >
>
>

 

[richard waters]

Emery,
I'm not tired of your reports. I've been there too (we've all been there),
trying to solve a problem that on the surface seems so easy. Reality however
is another thing. At least you are not alone. There are a couple of hundred of
us looking over your shoulders as you work and trying to help.

Richard Waters '76 PB, Troy, MI

>
> I'm sure some of you are a bit tired of hearing about my brake problems but I
> appreciate all your input and sometimes its just nice to have an outlet to
> vent your frustrations.
>
> Emery Stora
> 77 Kingsley
> Santa Fe, NM
>
> Emery Stora
> 77 Kingsley
> Santa Fe, NM
>
> Emery Stora

 

[david l greenberg]

I have tried to stay out of this bleeding problem since I have no
personal experience to add and there seems to be lots of offers of advice
already.

At our Sunshine Statesmen Tech Session this weekend the question was
raised by two members who have just installed their own all wheel disk
brake system with parts from TSM and others.

They spent two weeks trying to bleed the brakes until they found out they
had to bleed each wheel individually by blocking off each section of the
master cylinder and disconnecting and plugging each brake line but for
one. They also said they started by bleeding the M.C. first.

Ron Tase was invloved in solving this problem and for consultation
contact him at tasegmc31 I may be wrong on some of the points so
get with Ron.

David Lee Greenberg
GMC Motorhome Registry
200 Macfarlane Drive PH 4
Delray Beach, FL 33483-6829
800-827-9989

 

[john dolan]

Thanks Dave...
I'm glad you decided to pass that on, as I need to do brakes but have
been putting it off because of the stories, one after another. I guess
we may not hear about the successful bleeds, because it would seem too
nonplus to be reporting (at least before this collection of war stories)

> they had to bleed each wheel individually by blocking off each section
> of the master cylinder and disconnecting and plugging each brake line
> but for one.

I'm not ready enough to have Ron go though a detailed explanation, but
let me ask if anyone does get one from Ron... maybe ask him if we can all
share his method and have it posted here on the net rather than each of
us asking individually. I would be interested in opinions as to how hard
or easy it would be to accomplish the the above quoted isolation
technique.

- --
"I do whatever my Rice Krispies tell me to..." John said.