Resetting proportional valve

[67/6barracuda]

Guys I’m pulling my hair trying to bleed these brakes on a 71 duster that sat for years 9” drums. Im only getting fluid to the drivers front bleeder. The other 3 are dry getting nothing. It was parked because of a brake issue before I got it. I replaced master cylinder because the original was frozen up with rust. I’m guessing the proportional valve is stuck or clogged. I tried blowing air in the lines to reset it but not working. Any other tricks out there or I’m stuck replacing everything?

 

[halifaxhops]

If there is like a rod out of a plastic or metal nut for lack of a better term depress it and then hit the brakes it will flush it out.

 

[Murray]

If we are talking about the distribution block, that bias valve for unequal front/rear pressure, that needs to be disassembled to be re-centered.

 

[Oldmanmopar]

Drum brakes don't have a proportion valve. You need to take the distribution block off and clean the dirt out. Also take all the lines off and blow them out.

Improper installation of a master cylinder will prevent it from applying the rear brakes if the piston in the master is not returning all the way.

The other front wheel may have a blockage from the block to the wheel or the bleeder may be clogged

 

[67/6barracuda]

Yes correct distribution block. 71’ do not have the proportional valve. Problem I’m having is the lines are rusted solid to the distribution block. I hit it with some penetration oil but they are showing their age. I’ll more than likely replace the distribution with a new one and replace most of the lines I spent 2 days already trying to bleed these darn things. I appreciate the answers. i will still investigate the d-block when I get it off, I’ll more than likely have to cut the lines to do so.

 

[CRUZE 418]

Keep and clean your old distribution block, the new replacements can be a real piece of chinesium junk. Replace all of your brake lines with a kit from inline tube or other supplier. Replace all of the rubber hoses too. What kind of shape is the whole fuel system in?

 

[67/6barracuda]

I was able to get the D-block off. It did indeed need to be reset and cleaned out. Got it back together. I tried to blow the lines out on the front passenger with the d-block off and it was not passing air. Im guessing either the wheel cylinder is clogged up or line is clogged, yes the bleeder was open. I’ll try again next weekend.

I already replaced the fuel tank and blew out the gas lines. It should be good to go.

Thanks for the help

 

[67Dart273]

Back in the day I recall you could buy a tool to force them to remain centered. You unscrewed the switch, and replaced it with this tool, just a little threaded, knurled gizmo with a stem to mimic the switch stem.