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Poor Braking [message #98017] Tue, 31 August 2010 23:18 Go to next message
LEdmcconnell is currently offline  LEdmcconnell   United States
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Registered: November 2004
Location: Bridgeton, MO
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Junior Member
I have to really stand on the brakes to get the coach to stop. I thought the problem was the brake booster, but I checked it by starting the motor & pulling the check valve. It had vacuum. I replaced it & shut off the motor before removing the valve again. I heard air rushing into the booster. Does this mean the booster is OK? If not, what other test can I give? If the booster is alright, where else should I look?



Luther McConnell
'76 Birchaven
Bridgeton, MO
Re: [GMCnet] Poor Braking [message #98032 is a reply to message #98017] Wed, 01 September 2010 07:31 Go to previous messageGo to next message
Steven Ferguson is currently offline  Steven Ferguson   United States
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Registered: May 2006
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Senior Member
A leaking wheel cyl will soak the brake shoes with fluid and add a
tremendous amount of pedal effort to stop. A leak from a wheel cyl is
easy to find as there is usually brake fluid on the outside of the
drums and on the wheels where it was thrown by centrifigul force.
Check the MC level also.

On Tue, Aug 31, 2010 at 9:18 PM, LEdmcconnell <LEdmcconnell@aol.com> wrote:
>
>
> I have to really stand on the brakes to get the coach to stop.  I thought the problem was the brake booster, but I checked it by starting the motor & pulling the check valve.  It had vacuum.  I replaced it & shut off the motor before removing the valve again.  I heard air rushing into the booster.  Does this mean the booster is OK?  If not, what other test can I give? If the booster is alright, where else should I look?
>
>
> --
> Luther McConnell
> '77 Birchaven
> Bridgeton, MO
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
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>



--
Steve Ferguson
'76 EII
Sierra Vista, AZ
Urethane bushing source
www.bdub.net/ferguson/
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Re: Poor Braking [message #98047 is a reply to message #98017] Wed, 01 September 2010 10:04 Go to previous messageGo to next message
Bob de Kruyff   United States
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Registered: January 2004
Location: Chandler, AZ
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Senior Member
LEdmcconnell wrote on Tue, 31 August 2010 22:18

I have to really stand on the brakes to get the coach to stop. I thought the problem was the brake booster, but I checked it by starting the motor & pulling the check valve. It had vacuum. I replaced it & shut off the motor before removing the valve again. I heard air rushing into the booster. Does this mean the booster is OK? If not, what other test can I give? If the booster is alright, where else should I look?



Sounds like the booster is probably OK. I would check to make sure both front and back systems are working. Check the master cylinder fluid. Next I would adjust the rear brakes.


Bob de Kruyff
78 Eleganza
Chandler, AZ
Re: Poor Braking [message #98054 is a reply to message #98047] Wed, 01 September 2010 10:46 Go to previous messageGo to next message
gbarrow2 is currently offline  gbarrow2   United States
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Location: Lake Almanor, Ca./ Red Bl...
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Senior Member
What Bob said. Especially about adjusting the rear.
The front working alone will not stop the coach. Properly adjusted, the rears will make a big difference.


Gene Barrow
Lake Almanor, Ca.
1976 Palm Beach
Re: Poor Braking [message #98056 is a reply to message #98054] Wed, 01 September 2010 11:19 Go to previous messageGo to next message
WD0AFQ is currently offline  WD0AFQ   United States
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Registered: November 2004
Location: Dexter, Mo.
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Senior Member
Luther, what Bob said. remember he fixed my braking problem back in the winter. It was no fun driving from Dallas to Az, through El Paso with no brakes. Bob replaced my MC and adjusted my rear brakes. I also put on the sensatized booster from Jim K. My brakes are very good again. The sens. booster does not make the brakes better but it makes them so you just touch the pedal, like a car, and the thing stops. Used to really have to apply force to the pedal.
Dan
still got an lp leak and hope yall can sniff it out in Du Quoin


3 In Stainless Exhaust Headers One Ton All Discs/Reaction Arm 355 FD/Quad Bag/Alum Radiator Manny Tran/New eng. Holley EFI/10 Tire Air Monitoring System Solarized Coach/Upgraded Windows Satelite TV/On Demand Hot Water/3Way Refer
Re: [GMCnet] Poor Braking [message #98141 is a reply to message #98056] Wed, 01 September 2010 22:06 Go to previous messageGo to next message
gmc gmc is currently offline  gmc gmc   United States
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humm ok maybe my rear brakes need adjusting. How do I do that?

I have not had time, and little scared to take back wheels off. Are
bearing hard to repack?

thanks

Mike Derr
Madison, WI
78 refurbished.

On Wed, Sep 1, 2010 at 12:19 PM, Dan Gregg <gregg_dan@hotmail.com> wrote:

>
>
> Luther, what Bob said. remember he fixed my braking problem back in the
> winter. It was no fun driving from Dallas to Az, through El Paso with no
> brakes. Bob replaced my MC and adjusted my rear brakes. I also put on the
> sensatized booster from Jim K. My brakes are very good again. The sens.
> booster does not make the brakes better but it makes them so you just touch
> the pedal, like a car, and the thing stops. Used to really have to apply
> force to the pedal.
> Dan
> still got an lp leak and hope yall can sniff it out in Du Quoin
> --
> Dan & Teri Gregg
>
> http://danandteri.blogspot.com/
>
>
>
>
> _______________________________________________
> GMCnet mailing list
> List Information and Subscription Options:
> http://temp.gmcnet.org/cgi-bin/mailman/listinfo/gmclist
>
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Re: [GMCnet] Poor Braking [message #98162 is a reply to message #98141] Thu, 02 September 2010 04:26 Go to previous message
Ken Burton is currently offline  Ken Burton   United States
Messages: 10030
Registered: January 2004
Location: Hebron, Indiana
Karma: 10
Senior Member
gmc gmc wrote on Wed, 01 September 2010 22:06

humm ok maybe my rear brakes need adjusting. How do I do that?

I have not had time, and little scared to take back wheels off. Are
bearing hard to repack?

thanks

Mike Derr
Madison, WI
78 refurbished.

On Wed, Sep 1, 2010 at 12:19 PM, Dan Gregg <gregg_dan@hotmail.com> wrote:

>
>
> Luther, what Bob said. remember he fixed my braking problem back in the
> winter. It was no fun driving from Dallas to Az, through El Paso with no
> brakes. Bob replaced my MC and adjusted my rear brakes. I also put on the
> sensatized booster from Jim K. My brakes are very good again. The sens.
> booster does not make the brakes better but it makes them so you just touch
> the pedal, like a car, and the thing stops. Used to really have to apply
> force to the pedal.
> Dan
> still got an lp leak and hope yall can sniff it out in Du Quoin
> --
> Dan & Teri Gregg
>
> http://danandteri.blogspot.com/




Back brakes adjust just like any other drum brakes. You raise the wheel just enough to be able to spin it. Reach in the adjusting hole in the rear backing plate with a brake adjusting tool. Crank in the adjuster until you just hear or feel a very slight drag. Do all 4 and you are done. They are suppose to self adjust when you back up. How many times to you backup ? Probably not many.




Ken Burton - N9KB
76 Palm Beach
Hebron, Indiana
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