HOW DO I FIX BRAKE PROPORTIONING VALVE 1983? No fluid/pressure to front right caliper

[83v6Stock]

SECOND POST 1983 v6 sat for 15 years, while rust never sleeps. I get no fluid out of the brake proportioning valve to the front right/passenger side. Fluid and pressure are good to driver's side disc brake when brake pedal is depressed. Pressure goes to RR brake too. Is there a rebuild or fix for the brake proportioning valve?

I conclude that the master cylinder is working fine.

[83v6Stock]

SECOND POST 1983 v6 sat for 15 years, while rust never sleeps. I get no fluid out of the brake proportioning valve to the front right/passenger side. Fluid and pressure are good to driver's side disc brake when brake pedal is depressed. Pressure goes to RR brake too. Is there a rebuild or fix for the brake proportioning valve?

I conclude that the master cylinder is working fine.

[Ford1]

SECOND POST 1983 v6 sat for 15 years, while rust never sleeps. I get no fluid out of the brake proportioning valve to the front right/passenger side. Fluid and pressure are good to driver's side disc brake when brake pedal is depressed. Pressure goes to RR brake too. Is there a rebuild or fix for the brake proportioning valve?

I conclude that the master cylinder is working fine.

Proportioning valves can't be fixed or repaired, just get a used one, I bought one online from a junk yard they shipped it. It was in great shape.

[83v6Stock]

Thanks for the tip.Iused a pick about the size of a toothpick to clear the crud out of the blockednozzle.I first tried compressed airthrough the 3 holes in the front brake chamber.Then removed all 6 brake lines 7/16^th” and 2 ½” nuts toremove the brake valve.I completelydisassembled, cleaned and reassembled the valve.The rain drove me indoors.I expect to have it reassembled soon.

[erratic50]

As a person who nearly crashed his fox recently due to a brake problem - my suggestion is to be exceptionally careful or just don't mess with fixing rather than replacing at all.

if parts are used and not part of a sealed system consider them cores!

I removed the valve and put in a plug on my 86 GT along with 1999 GT calipers and drilled/slotted rotors plus Summit proportioning valve and a 1995 GT rear ended and MarkVII master cyl, braded hoses, etc. What happened to me was one of the low miles used 99GT calipers hung up. Not bad but enough that at 45 MPH it generated enough heat to boil the brake fluid which caused my brakes to simply go to the floor when I needed them.

the main place of extreme heat transfer was the stock proportioning valve. Both front and rear boiled and it didn't drive in a way that you could tell there was a hang up.

I am not so sure I would go the plug route next time - line locks for the front are cheap. Those plus a proportioning valve eliminates the stock proportioning valve entirely. Use a newer master cyl if you want a low fluid sensor.

[qikgts]

A proportioning valve seal kit is available below... They can be taken apart, cleaned and then resealed as has been mentioned in this thread.

https://www.musclecarresearch.com/va...-E0ZC-2B328-AA

Instructions are here...

https://www.musclecarresearch.com/E0ZC-2B328-AA-rebuild

[wraithracing]

As mentioned, Proportioning valves can be cleaned and resealed. You will want to take extra care and pay close attention to the assembly order of the valve to make sure you re-assemble it correctly.

If you do replace a proportioning valve you want to make sure that you do so with the exact same unit as the valves are based upon vehicle specifications and swapping valves without knowing what it came off of or what it was originally designed for is not a good idea.

If you make significant changes to the brake system such as different size calipers or rear disc instead of drums then removal of the OEM proportioning valve and the installation of an adjustable unit is what is needed in order to balance the front and rear bias in the brake system. This is needed to make sure that your rear brakes do not grab before your front brakes which can be very dangerous and cause you to wreck your vehicle.

[83v6Stock]

Thanks for the tips guys. Rust never sleeps.After 15 years, there’s more, and the waterabsorbing character of brake fluid must have seriously trapped h2o in mysystem. So, I am replacing the frontcalipers, rear wheel cylinders, and master cylinder.Some of the brake metal line malefittings/fluid carrying bolts are really stuck.

I found out a rear wheel cylinder was not working partiallyby brake pedal feel while bleeding.Igot fluid out of the bleeder, but the brake pedal would not go to the floor.I had replaced a caliper, and the pedal wentto the floor while bleeding.