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another brake question [message #371541] Sun, 26 November 2023 13:03 Go to next message
skip2 is currently offline  skip2   United States
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After talking to Mr. Stone about his setup I started looking at my brass combination valve. When I got the coach 12 years ago the PO had made a fixture to hold down what I thought was the reset valve, on the front, all the time, anyone know what effect this will have. Also noticed that the valve hex body on the rear has what looks like a relief valve which is held in place with a star washer pressed in. I've read elsewhere that someone actually lost their rear brakes when this valve popped out, anyone know the function of this thing is. Any input or directions would be appreciated.

74 Canyon Lands, FiTech, 3.7 FD LSD, Manny Tranny, Springfield Distributor, 2001 Chevy Tracker Ragtop Towd
Re: another brake question [message #371542 is a reply to message #371541] Mon, 27 November 2023 07:00 Go to previous messageGo to next message
jhbridges is currently offline  jhbridges   United States
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The 'button' is held down during bleeding the brakes to keep the shuttle valve centered. Remove the fixture for normal use.

The OEM valve does not proportion in the Motorhome, it merely slows activation of the front discs until the rear shoes are extended to the drums. The car valves reduce pressure to the rear, this must be disabled to use a car valve in a Motorhome.

Search GMCMI archives for Dave Lenzi's article(s) on Motorhome brakes, he's the guru.

--johnny


Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons. Braselton, Ga. I forgive them all, save those who hurt the dogs. They must answer to me in hell

[Updated on: Mon, 27 November 2023 07:02]

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Re: another brake question [message #371546 is a reply to message #371541] Wed, 29 November 2023 11:05 Go to previous message
wally is currently offline  wally   United States
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skip2 wrote on Sun, 26 November 2023 13:03
After talking to Mr. Stone about his setup I started looking at my brass combination valve. When I got the coach 12 years ago the PO had made a fixture to hold down what I thought was the reset valve, on the front, all the time, anyone know what effect this will have. Also noticed that the valve hex body on the rear has what looks like a relief valve which is held in place with a star washer pressed in. I've read elsewhere that someone actually lost their rear brakes when this valve popped out, anyone know the function of this thing is. Any input or directions would be appreciated.
Lenzi's article on combination valves starts on page 24 here
https://issuu.com/kimweeks04/docs/gmc_vintage_rving-2021_winter
https://issuu.com/kimweeks04/docs/gmc_vintage_rving-2021_winter


Wally Anderson
Omaha NE
75 Glenbrook
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