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Old 04-29-2012, 05:29 PM   #11
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Join Date: Oct 2008
Location: Prosper Texas
Posts: 696
Re: Resetting a 67 distribution block ?

The valve in question for a drum/drum brake system is a pressure differential valve. It has a valve in it that will stay centered with equal pressure front and rear. It will move to one way or the other if one end of the brake system has a pressure drop, this will provide a ground circuit to the brake warning lamp and it will light up notifying the driver that there has been a brake pressure loss. When the loss of pressure is repaired the valve can be recentered by firmly depressing the brake pedal a couple of times.
68 SWB, Dad bought new
63 Impala Sport Sedan
64 Impala SS, 409 425HP
64 Bel Air Wagon
57 Bel Air w/Factory Air
77 GMC Sprint, 454/425HP
67 Olds 442, all original
80 Olds 98, Mom's old car
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