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Breaks [message #66052] Mon, 30 November 2009 07:21 Go to next message
Bill Backouris is currently offline  Bill Backouris   United States
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Had a great time camping over Thanksgiving holiday, all went well until on freeway going 45 and no breaks down to the floor nothing, put in neutral started pumping like crazy and built up enough pressure to bring me to a stop, limped off the freeway and was able to make it home at about 15mph pumping like crazy, is the thought I might have blown a break line, or wheel cylinder, break resivour was a little low, any thoughts would be great
Bill Backouris
77 Birchaven 455
Garden Grove Ca
Re: Breaks [message #66055 is a reply to message #66052] Mon, 30 November 2009 07:29 Go to previous messageGo to next message
Rick Williams is currently offline  Rick Williams   United States
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Bill
The first thing to check for are leaks. You said the fluid was "a little low". That may not mean anything. Check all wheels and lines for fluid. If you do not find any, it could be a bad master cylinder. Check for leaks and let us know.
Rick


Rick Williams
Bliss, Michigan
1978 Eleganza II
Re: Breaks [message #66056 is a reply to message #66052] Mon, 30 November 2009 07:29 Go to previous messageGo to next message
John Sharpe is currently offline  John Sharpe   United States
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Quote:

Bill Backouris wrote:
Had a great time camping over Thanksgiving holiday, all went well until on freeway going 45 and no breaks down to the floor nothing, put in neutral started pumping like crazy and built up enough pressure to bring me to a stop, limped off the freeway and was able to make it home at about 15mph pumping like crazy, is the thought I might have blown a break line, or wheel cylinder, break resivour was a little low, any thoughts would be great


My initial thought is a defective master cylinder. With all that pumping I would think you would be out of fluid if you had a leak.


John Sharpe
Humble,TX
'78 Eleganza TBI
'89 Spectrum 2000 MPI V-10
'40 Ford Panel Delivery TPI
johnasharpe@gmail.com
Re: Breaks [message #66060 is a reply to message #66052] Mon, 30 November 2009 07:37 Go to previous messageGo to next message
Bill Backouris is currently offline  Bill Backouris   United States
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John, thank you, thats a good point my nerves were certinly on edge and frantic pumping should have drained the cylinder
Bill
Re: Breaks [message #66061 is a reply to message #66055] Mon, 30 November 2009 07:38 Go to previous messageGo to next message
Bill Backouris is currently offline  Bill Backouris   United States
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Thanks Rick, will get back to you on my findings
Bill
Re: [GMCnet] Breaks [message #66062 is a reply to message #66052] Mon, 30 November 2009 07:48 Go to previous messageGo to next message
GMCWiperMan is currently offline  GMCWiperMan   United States
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Bill,

If you didn't lose fluid, the problem is almost certainly the MC. Even then
it's surprising that the pedal went all the way to the floor: You should
have still had either front or rear brakes; the pedal would have been low,
but if the rear brakes failed you should have still had good braking from
the fronts. More likely, the front system failed and the rear brakes were
so badly out of adjustment that they allowed the pedal to bottom out.
Please let us know what you learn.

By the way: If I had a brake failure, I would NOT go to Neutral until
almost stopped: Selecting Low would be my reaction because the engine
braking would be a big help down to 15 mph or so. JWID.

Ken H.

On Mon, Nov 30, 2009 at 8:21 AM, Bill Backouris <bkbackouris@hotmail.com>wrote:

>
>
> ... on freeway going 45 and no breaks down to the floor nothing, put in
> neutral started pumping like crazy and built up enough pressure to bring me
> to a stop, limped off the freeway and was able to make it home at about
> 15mph pumping like crazy, is the thought I might have blown a break line, or
> wheel cylinder, break resivour was a little low, any thoughts would be great
>
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Re: [GMCnet] Breaks [message #66063 is a reply to message #66052] Mon, 30 November 2009 07:51 Go to previous messageGo to next message
Gary Casey is currently offline  Gary Casey   United States
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Can't help much, but I sure hope my breaks never brake...oops.  Sorry, couldn't help myself :-)

Actually, one thing that I don't think was mentioned by the others is that a rotor, if warped badly, will "knock back" the pistons and then the pedal will drop.  Don't think that is your problem, though.
Gary



________________________________
From: Bill Backouris <bkbackouris@hotmail.com>
To: gmclist@temp.gmcnet.org
Sent: Mon, November 30, 2009 6:21:25 AM
Subject: [GMCnet] Breaks



Had a great time camping over Thanksgiving holiday, all went well until on freeway going 45 and no breaks down to the floor nothing, put in neutral started pumping like crazy and built up enough pressure to bring me to a stop, limped off the freeway and was able to make it home at about 15mph pumping like crazy, is the thought I might have blown a break line, or wheel cylinder, break resivour was a little low, any thoughts would be great
Bill Backouris
77 Birchaven 455
Garden Grove Ca
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Re: Breaks [message #66064 is a reply to message #66052] Mon, 30 November 2009 07:57 Go to previous messageGo to next message
Bill Backouris is currently offline  Bill Backouris   United States
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Ken, I was just a little concerned going into low at 45
Bill
Re: [GMCnet] Breaks [message #66070 is a reply to message #66060] Mon, 30 November 2009 08:36 Go to previous messageGo to next message
Jim Bounds is currently offline  Jim Bounds   United States
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Boy, thats the "Breaks" with brakes (no pun)!  You never think much about them until you don;t have any!  Sounds like you were testing a new "air barke" system.  If you had total failure, n ot just fronts or rears it does sound like a master cylinder but let me suggest something-- as important as brakes are as you found out don;t just diagnose and fix what failed, there may be other components of the system that are reacing the end of their reliability envelope-- go through the whole thing!  Maybe flames will shoot out from the motor but at least your brakes will bring you to a stop! 

I see it often that coaches sit around and are used only when we take a trip-- heck, I do that and when we get out there the brakes fail for many reasons.  Sitting or driving, brakes and other systems go about degrading.  If you have done hoses, wheel cylinders, spring kits, checking steel lines, master cylinder even a vacuum backup there is still flushing the fluid.  Brakes are a constant issue and as important as you found they are man you just don;t wanna rely on "they worked when I left".

Don;t feel bad or get upset, I am probably a worse offender.  Just cause my coach sits here at the shop while I work on other peoples brakes-- mine will not fix themselves via "osmosis"!  A big part of keeping these puppies running is keeping them stopping--- thats the breaks!

Jim Bounds
-----------------------



----- Original Message ----
From: Bill Backouris <bkbackouris@hotmail.com>
To: gmclist@temp.gmcnet.org
Sent: Mon, November 30, 2009 8:37:40 AM
Subject: Re: [GMCnet] Breaks



John, thank you, thats a good point my nerves were certinly on edge and frantic pumping should have drained the cylinder
Bill
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Re: [GMCnet] Breaks [message #66088 is a reply to message #66064] Mon, 30 November 2009 11:18 Go to previous messageGo to next message
GMCWiperMan is currently offline  GMCWiperMan   United States
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Bill,

You can always go to "S" first. But, fact is, at 45 -- or 65 -- you could
still shift to "L" and the transmission would shift into 2nd immediately,
but not into 1st until approximately 40 mph (see the operator's manual).
Not the best way to operate, but preferable to coasting with no brakes. :-)
And if you match the engine speed well, not that hard on the transmission
-- it's how I routinely drive in the mountains.

HTH,

Ken H.

On Mon, Nov 30, 2009 at 8:57 AM, Bill Backouris <bkbackouris@hotmail.com>
wrote:

>
>
> Ken, I was just a little concerned going into low at 45
> Bill
> _______________________________________________
>
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Re: Breaks [message #66102 is a reply to message #66052] Mon, 30 November 2009 12:21 Go to previous messageGo to next message
Bill Backouris is currently offline  Bill Backouris   United States
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Thank you all, I was looking at Jim K's site and see he has a 6 wheel disk break conversion. In looking at my situation and knowing how I am, I will want new breaks all around with new booster and MS. Would money be better spent and upgrade to the disk conversion? I would appreciate your thoughts

Thanks Bill
Re: [GMCnet] Breaks [message #66122 is a reply to message #66070] Mon, 30 November 2009 15:03 Go to previous messageGo to next message
Bill Backouris is currently offline  Bill Backouris   United States
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Jim, thats what I was thinking infact I am concidering the complete disk break conversion, you are correct it does seem like breaks take a back seat to other things until we step on the pedel and nothing. The disk conversion something that we can do in our driveway with a little patience????

Thanks
Bill Backouris
77 Birchaven 455
Garden Grove Ca
Re: [GMCnet] Breaks [message #66125 is a reply to message #66088] Mon, 30 November 2009 15:04 Go to previous messageGo to next message
Chuck Garton is currently offline  Chuck Garton   United States
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If the transmission has a valve body upgrade "kit" installed, it will
go into low at any speed by puling the lever into low.

In an emergency, one could aviod hitting something at the cost of an engine.

One way to tell if a "kit" is installed; with a working kickdown
system, drive about 25 - 30 MPH and floor the gas pedal.

If it goes into 2nd (S); no "kit." If it goes into 1st; "kit" is installed.

Chuck Garton
77 Kingsley 455
Ridgecrest, CA

On Mon, Nov 30, 2009 at 9:18 AM, Ken Henderson <ken0henderson@gmail.com> wrote:
> Bill,
>
> You can always go to "S" first.  But, fact is, at 45 -- or 65 -- you could
> still shift to "L" and the transmission would shift into 2nd immediately,
> but not into 1st until approximately 40 mph (see the operator's manual).
>  Not the best way to operate, but preferable to coasting with no brakes. :-)
>  And if you match the engine speed well, not that hard on the transmission
> -- it's how I routinely drive in the mountains.
>
> HTH,
>
> Ken H.
>
> On Mon, Nov 30, 2009 at 8:57 AM, Bill Backouris <bkbackouris@hotmail.com>
>  wrote:
>
>>
>>
>> Ken, I was just a little concerned going into low at 45
>> Bill
>> _______________________________________________
>>
> _______________________________________________
> GMCnet mailing list
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>
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Re: [GMCnet] Breaks [message #66128 is a reply to message #66125] Mon, 30 November 2009 15:16 Go to previous messageGo to next message
Mr ERFisher is currently offline  Mr ERFisher   United States
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really hard on bands and clutches, manny will hate it

gene



On Mon, Nov 30, 2009 at 1:04 PM, Chuck Garton <chuck210@gmail.com> wrote:

> If the transmission has a valve body upgrade "kit" installed, it will
> go into low at any speed by puling the lever into low.
>
> In an emergency, one could aviod hitting something at the cost of an
> engine.
>
> One way to tell if a "kit" is installed; with a working kickdown
> system, drive about 25 - 30 MPH and floor the gas pedal.
>
> If it goes into 2nd (S); no "kit." If it goes into 1st; "kit" is installed.
>
> Chuck Garton
> 77 Kingsley 455
> Ridgecrest, CA
>
> On Mon, Nov 30, 2009 at 9:18 AM, Ken Henderson <ken0henderson@gmail.com>
> wrote:
> > Bill,
> >
> > You can always go to "S" first. But, fact is, at 45 -- or 65 -- you
> could
> > still shift to "L" and the transmission would shift into 2nd immediately,
> > but not into 1st until approximately 40 mph (see the operator's manual).
> > Not the best way to operate, but preferable to coasting with no brakes.
> :-)
> > And if you match the engine speed well, not that hard on the
> transmission
> > -- it's how I routinely drive in the mountains.
> >
> > HTH,
> >
> > Ken H.
> >
> > On Mon, Nov 30, 2009 at 8:57 AM, Bill Backouris <bkbackouris@hotmail.com
> >
> > wrote:
> >
> >>
> >>
> >> Ken, I was just a little concerned going into low at 45
> >> Bill
> >> _______________________________________________
> >>
> > _______________________________________________
> > GMCnet mailing list
> > List Information and Subscription Options:
> > http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
> >
> _______________________________________________
> GMCnet mailing list
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>



--
Gene Fisher -- 74-23,77PB/ore/ca
“Give a man a fish; you have fed him for today --- give him a URL and
-------
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Re: [GMCnet] Breaks [message #66144 is a reply to message #66122] Mon, 30 November 2009 16:48 Go to previous messageGo to next message
Rick Denney is currently offline  Rick Denney   United States
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Bill Backouris writes...



> Jim, thats what I was thinking infact I am concidering the complete
> disk break conversion, you are correct it does seem like breaks take
> a back seat to other things until we step on the pedel and nothing.
> The disk conversion something that we can do in our driveway with a little patience????

It's hard to tell what the mechanical skills are others are.

Installing disk brakes requires quite a lot of work. You'll need a new
master cylinder, proportioning valve (or a modification to the current
one), backing plates and brakes for the rear wheels, and some means of
establishing a parking brake, which the disk brakes will eliminate.
You'll also have to replace anything else that needs replacing,
including front brakes, hoses, lines, and booster. So, it's a matter
of pulling the brake drum so that you can replace the wheel cylinder
and shoes, or pulling the drum, spindle, and backing plate so that you
can start over with a new backing plate, hub, rotor, and caliper.

I would say that for me doing the work myself, replacing everything
with stock would take a day and cost in the hundreds. Upgraded to disk
brakes would take several full days and cost in the thousands. I would
not make that change just because stuff is broken and needs to be
fixed--I would make that change only because I want better brakes, or
because I want the ability to install Chuck Aulgur's reaction rod
(another expensive but slick modification). The stock brakes are not
that great, but lots of people (including me) do use them and they
work.

Rick "not thinking this falls into the 'might as well' category"
Denney

'73 230 Ex-Glacier "Jaws"
Northern Virginia

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'73 Glacier 230 "Jaws"
Re: [GMCnet] Breaks [message #66154 is a reply to message #66144] Mon, 30 November 2009 18:17 Go to previous messageGo to next message
Bill Backouris is currently offline  Bill Backouris   United States
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Something to think about Rick, don't want to impulse buy, but I was so concerned for my wifes safety but also for anyone else I might have taken out, so is it your thought that a complete brake job using the current drum brake set up, new booster, ms pads lines etc would give me adequate stopping power and most importantly relability
Thanks Bill
Re: [GMCnet] Breaks [message #66157 is a reply to message #66144] Mon, 30 November 2009 18:31 Go to previous messageGo to next message
Rick Denney is currently offline  Rick Denney   United States
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Rick Denney writes...

> It's hard to tell what the mechanical skills are others are.

Sheesh, it's a good thing I didn't say anything about the spelling of
"brakes". That sentence richly deserves widespread ridicule.

Rick "you know what I meant...maybe" Denney

'73 230 Ex-Glacier "Jaws"
Northern Virginia

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'73 Glacier 230 "Jaws"
Re: Breaks [message #66158 is a reply to message #66052] Mon, 30 November 2009 18:35 Go to previous messageGo to next message
fred v is currently offline  fred v   United States
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i remember reading in GMC history somewhere that they tested the tranny by going to WOT and shifting from D to R 100 times. the tranny survived this! can you imagine that?


Fred V
'77 Royale RB 455
P'cola, Fl
Re: [GMCnet] Breaks [message #66161 is a reply to message #66154] Mon, 30 November 2009 18:40 Go to previous messageGo to next message
Rick Denney is currently offline  Rick Denney   United States
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Bill Backouris writes...

> Something to think about Rick, don't want to impulse buy, but I was
> so concerned for my wifes safety but also for anyone else I might
> have taken out, so is it your thought that a complete brake job
> using the current drum brake set up, new booster, ms pads lines etc
> would give me adequate stopping power and most importantly relability

Yes, "adequate" and "reliable" seem to me like appropriate
descriptions for the original brake system when in good condition. My
brakes were all gone through by the PO, including new cylinders,
hoses, and master cylinder (but nothing else), and in five years I've
replaced the front pads once and replaced the fluid, but I have had no
failures or other issues.

Of course, "adequate" is subject to interpretation. Anyone who runs
into anything, or even comes close, will often conclude that the
brakes were inadequate. But even with disk brakes, we can't drive
these coaches like they are modern passenger cars with ABS. We still
have to leave extra stopping distance and pay attention to our
situation.

Rick "thinking stock brakes in good order give a safe driver plenty to
work with" Denney

'73 230 Ex-Glacier "Jaws"
Northern Virginia

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'73 Glacier 230 "Jaws"
Re: [GMCnet] Breaks [message #66163 is a reply to message #66161] Mon, 30 November 2009 18:51 Go to previous messageGo to previous message
C Boyd is currently offline  C Boyd   United States
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Rick Denney wrote on Mon, 30 November 2009 19:40

Bill Backouris writes...

> Something to think about Rick, don't want to impulse buy, but I was
> so concerned for my wifes safety but also for anyone else I might
> have taken out, so is it your thought that a complete brake job
> using the current drum brake set up, new booster, ms pads lines etc
> would give me adequate stopping power and most importantly relability

Yes, "adequate" and "reliable" seem to me like appropriate
descriptions for the original brake system when in good condition. My
brakes were all gone through by the PO, including new cylinders,
hoses, and master cylinder (but nothing else), and in five years I've
replaced the front pads once and replaced the fluid, but I have had no
failures or other issues.

Of course, "adequate" is subject to interpretation. Anyone who runs
into anything, or even comes close, will often conclude that the
brakes were inadequate. But even with disk brakes, we can't drive
these coaches like they are modern passenger cars with ABS. We still
have to leave extra stopping distance and pay attention to our
situation.

Rick "thinking stock brakes in good order give a safe driver plenty to
work with" Denney

'73 230 Ex-Glacier "Jaws"
Northern Virginia

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C. Boyd
76 Crestmont
East Tennessee
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