1976 Gmc Truck 76 K1500 Replaced Calipers Drums Master Cyl Factory

1976 GMC TRUCK
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GADMAN
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76 gmc k1500, have replaced calipers, drums, master cyl & factory perportioning valve. have no front brakes & rears lock up. after repeated checks it appears the perportioning valve is not centered? is there a way to reset it ? other ideas ? could the lines in be swapped &
Oct 17, 2012 at 4:45 PM
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JDL
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Did you bleed the brakes? The pin on the proportioning vavle should be held open during bleeding.
Oct 17, 2012 at 4:54 PM
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GADMAN
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yes, how do you hold the pin open ? have never heard of that before & can it be reset at this point?
Oct 17, 2012 at 5:53 PM
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JDL
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You can have a helper hold it open. There is a tool for that, use to be a tool. I believe in the past, I have used a small vice-grip to hold the pin. It's been a while since I worked on that model year.
Oct 17, 2012 at 6:43 PM
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GADMAN
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is the pin in the center of the brass plug on the lft side? there is not enough to get ahold of. if i were to loosen the plug & pull it will it center the valve? they have been bled several times & all lines are fresh fluid & no apparent air in system, just no pressure to the fronts. does the valve need pwr? i dont care about the light, hasnt worked in years.
Oct 17, 2012 at 7:03 PM
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JDL
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It's been a while, I'd have to look at it. That little pin, you either push it in or pull it out. I can't remember? I tried looking up that valve on an inline partsbook, couldn't find it. I thought maybe looking at the valve would jog my memory.
Oct 17, 2012 at 7:34 PM
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