Pressure Differential Valve Keeps Moving!

[BigFoot]

Ok,
Its finally done. The Key is to use the nifty tool to keep the valve from moving while bleeding.
I ended up taking the the valve off again and I put some red paint pen on the middle of the slider so that I could always take out the switch and look in the hole with a mirror and a flashlight to see it the valve is centered.
I put it all back together, bled it with the tool to hold the valve and its all good.

[cole71]

This would work without taking the valve out right? Just buying the tool, taking out the switch inserting it and bleeding the brakes, right?

[cole71]

My light is on and I'm thinking I might have to get the tool to recenter the valve.

[ultraranger]

My light is on and I'm thinking I might have to get the tool to recenter the valve.

The holding tool won't re-center the valve spool. The spool has to already be centered at the time the tool is inserted, prior to bleeding the brakes, in order to keep the spool centered during the bleeding process.

If the spool is already off-center, (brake warning light is on), you will have to open a bleeder screw opposite of the problem side. For instance, if the spool has shifted to the rear brake circuit side, you will have to crack open a bleeder screw on the front brakes, apply brake pressure on the pedal until the spool shifts back to the center position and turns the brake warning light off, then close the bleeder. At that point, you would remove the brake switch and insert the holding tool, on the centered valve spool, to begin bleeding the brake system.

[cole71]

Thanks for clearing that up ultraranger!

[BigFoot]

My light is on and I'm thinking I might have to get the tool to recenter the valve.

The holding tool won't re-center the valve spool. The spool has to already be centered at the time the tool is inserted, prior to bleeding the brakes, in order to keep the spool centered during the bleeding process.

If the spool is already off-center, (brake warning light is on), you will have to open a bleeder screw opposite of the problem side. For instance, if the spool has shifted to the rear brake circuit side, you will have to crack open a bleeder screw on the front brakes, apply brake pressure on the pedal until the spool shifts back to the center position and turns the brake warning light off, then close the bleeder. At that point, you would remove the brake switch and insert the holding tool, on the centered valve spool, to begin bleeding the brake system.

You got it!
Sorry, I didnt get back to the thread sooner. I'm glad ultraranger picked up my slack!

[cole71]

I bought the keeper to keep the valve center. Yesterday I got the light to go out. Thanks again guys!

[youngone]

I would imagine this would work for the disk brakes on the 73 to 79s.