Need help on 79 front brakes

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69farmer

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steve
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305
I have a 79 LWB that my dad bought new. It has been sitting in a shed and not started or moved since 07. I got it running good but front brakes are dragging. I just replaced the L&R calipers and rubber brake fluid hoses. I also sucked out the terrible looking fluid from the MC.
Now when i try to bleed it you have to take both feet to the pedal and push real hard and then you can feel the pedal go down with alot of resistance. And then when you are off of pedal the front brakes still drags and rotors are real hard to turn. Back brakes seems to work ok. Do i change the master cylinder or the proportioning valve? That is really all that is left aint it?
 

eskimomann209

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It was not hard to brake before you replaced the parts?
That doesn’t sound right.
Seems to me like maybe something was installed incorrectly. Like the pads are bound to the rotors before you even press on the brake pedal.
And you forcing it down is probably just beating up the master. You bled all 4 brakes?
Pictures would help a lot. I like to see what you’re doing.
There are some variations to 1” rotors and 1.25” rotors. I think 79 came with the 1.25 but If for some reason you had 1” and shoved in the larger ones. ... that might make it tight.
 

Rusty Nail

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Sounds like you may have installed the wrong parts.
You could check against the old ones if still around, but keep in mind not all 1979 front brakes are the same size. (10s or 11 or 12?)
More research is necessary.
Send pix.
What OTHER parts are listed available for that truck, there are options. I think you bought the wrong pads or something...:shrug:
 

PrairieDrifter

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If it didn't do it before the brake work, then the brake parts. If it did then I would say master cylinder.
 

fast 99

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Try pushing the pedal down with one or both bleeders open. There should be a decent squirt of fluid and minimal pedal effort until at least 1/2 way down. If little or no fluid at the calipers close the bleeders and try again with the lines cracked loose at the master. Suspect the master is bad or the lines are restricted somewhere. Personally, if it has been sitting that long I wouldn't use that master. Have also seen rubber hoses delaminate on the inside and appear perfectly fine on the outside.
 

idahovette

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He did the hoses ...see post #1 .....doesn't mean they can't be bad, but...
 

80BrownK10

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If it didn't do it before the brake work, then the brake parts. If it did then I would say master cylinder.
My thoughts are something wrong with the master cylinder as well. Rusty rod, bent or something similar. Like you said assuming everything else is installed and correct.
 

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