Shutter Valve/Combo Valve Stuck

[bmyohn]

Hey all,

I am in the process if bleeding my brakes now that I have one tons swapped in. I have an issue though. I some how have the shutter valve (in the proportioning valve) stuck to where the parking brake light is on and i am not getting any fluid to the rear lines.

What is the best way of getting the shutter/combo valve unstuck so that I can properly bleed my brakes?

Thanks!

 

[GrimmJeeper]

IIRC it is irreplaceable, once it pops it's done. it's there to save your ass if either the front or rear brakes lose pressure on the road. you may have to replace the proportioning valve.

 

[Talyn]

I haven't had this happen on a Jeep but it did on a dodge. What I did was unscrew the sensor on the prop valve, crank a bleed valve on a front caliper and have someone slowly apply pressure until the shuttle is recentered. You will want the rear sealed up of course. I have also heard of people moving the shuttle manually with a pick or screw driver to recenter it.

 

[O-Gauge Steamer]

If this proportion valve is like all of the others I have dealt with...

Remove the switch and gently aply the brakes to cause the shuttle to move back into position. This vavle changes state when there is a pressure differential in the legs and the switch then locks the valve into position as a safety measure. This switch turns on the "brake" light in the dash. It should be a spring loaded device so hang onto it when removing it. Not a lot of pressure, but some.

Heavy emphasis on gently here.

It should not be a one shot, throw it away. On some vehicles, 60s/70s Fords for instance, you can safely remove the switch to bleed the brakes.

Unless I am off base.