Prop valve?

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79K15 HIghSierra

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South Carolina
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Reuben
Truck Year
1979
Truck Model
K1500
Engine Size
350
Just did my rear brakes, new shoes and cylinders, but they won’t bleed! A little fluid trickles out but it doesn’t want to build up any pressure. I believe I need to “reset” my prop valve? It had run completely out of fluid in the rear (bad cylinder leaked out) so from what I’ve found, that will “trip” the valve? Any advice as far as reset or replace? Read somewhere you can open the front bleeders and mash the brakes to reset it? Thanks!
 

WebMonkey

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Chris
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K20
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Just did my rear brakes, new shoes and cylinders, but they won’t bleed! A little fluid trickles out but it doesn’t want to build up any pressure. I believe I need to “reset” my prop valve? It had run completely out of fluid in the rear (bad cylinder leaked out) so from what I’ve found, that will “trip” the valve? Any advice as far as reset or replace? Read somewhere you can open the front bleeders and mash the brakes to reset it? Thanks!

that's what i did.

in my 'progress thread', i rebuilt my rear drum brakes.
had a cylinder that leaked everything out.

after replacing everything on both sides, i opened the front driver's side bleeder wide open and then 'quick stomped' the brake pedal several times and the brake light went off.

(the brake bleeder had a hose pushed on it and run down into a jar of brake fluid).

close the front bleeder.

after that, the rear bled normally with smooth, slow presses of the brake pedal.

good luck
 

79K15 HIghSierra

Full Access Member
Joined
Nov 19, 2020
Posts
83
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175
Location
South Carolina
First Name
Reuben
Truck Year
1979
Truck Model
K1500
Engine Size
350
that's what i did.

in my 'progress thread', i rebuilt my rear drum brakes.
had a cylinder that leaked everything out.

after replacing everything on both sides, i opened the front driver's side bleeder wide open and then 'quick stomped' the brake pedal several times and the brake light went off.

(the brake bleeder had a hose pushed on it and run down into a jar of brake fluid).

close the front bleeder.

after that, the rear bled normally with smooth, slow presses of the brake pedal.

good luck

ok I will try this tomorrow! My truck sat for a while so I’m hoping the valve isn’t all gunked up. I’ll let you know!
 

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