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I know all the brake lines come off of this, but what is its function and what is it called? Also it it true you can not get this on the aftermarket? I am redoing all new brake lines. Do I need to do anything to it before I add the new lines? Thanks!
Basically, it distributed brake fluid to the front and rear systems. The electrical connector is a switch. When the systems are normal, there is a barrel that is between the two sides, with a detent for the switch. In the event that a brake line/wheel cylinder fails, the pressure from master cylinder forces the cylinder to one side or the other, blocking off the side with the failure, and triggering the switch to light the BRAKE warning on the dash.
Basically, it distributed brake fluid to the front and rear systems. The electrical connector is a switch. When the systems are normal, there is a barrel that is between the two sides, with a detent for the switch. In the event that a brake line/wheel cylinder fails, the pressure from master cylinder forces the cylinder to one side or the other, blocking off the side with the failure, and triggering the switch to light the BRAKE warning on the dash.
Do I need to do anything to it before I add new brake lines?
I'll bet that you could post a "What is this part?" thread with a picture of the part, in this forum at any time day or night, and have a correct response within thirty minutes!
In my experience no. But when bleeding the brakes you may have to hold open the adjuster at the end of it, on the right side of the picture.
Yeah, that itty bitty nipple looking thing. Used to be you could get a clip that slipped in place in that groove to hold it out while bleeding. I use small needle nose vice grips.
Just because the brakes are new (is the pro valve new?) the pro valve bleeded seal could be shot if it is original to the truck. Or the brake light warning light switch is another area notorious for leaking.
Just because the brakes are new (is the pro valve new?) the pro valve bleeded seal could be shot if it is original to the truck. Or the brake light warning light switch is another area notorious for leaking.
That valve is the one thing that didn't get replaced, mostly for reasons above. Everything else related to the brake system with the exception of the booster at least for now, was replaced. I only just caught it the other day crawling around underneath it. The truck doesn't move or even run right now anyways so I'm not super worried, but my guess is that seal is bad then. I am positive it is original to that truck. As I mentioned it stops just fine, sometimes almost too good.
Just because the brakes are new (is the pro valve new?) the pro valve bleeded seal could be shot if it is original to the truck. Or the brake light warning light switch is another area notorious for leaking.
Where exactly does the brake like warning switch wiring go to btw?
Slightly off topic... but the plug rests @ the proportioning valve location on the chassis... but where the heck does all the wiring go to from there? Anyone ever trace it back to somewhere inside the cab before?
I ask because I never did hook up my Wilwood adjustable Proportioning Valve's electronic brake warning light. Wasn't sure how to do it.
The Wilwood switch is not for a brake warning lamp. It's for brake lamps in case you need it. Like for a hot-rod installation where there is no existing brake light switch. In our case we don't need it unless the old switch has been deleted for some reason.
So it's just a pressure activated on-off switch. No way to have a pressure differential when there is only one circuit.
The original brake warning lamp however had a wire that came from the wiring harness with 12v when the key is on, and another wire to the ignition switch's "prove out" connector on the side of the switch. Separate from all the other wires.
A prove-out (or proof out) function simply grounds the switch body to the dash when it's in the START position. So like a modern car with warning light checks done by computer, this one simply shows you that the bulb is still working while the key is in the START position then goes back out when the key is returned back to ON or OFF positions.
On our older pressure switches with the two wires, the switch grounds through the frame when it senses a pressure change in one circuit. The new ones available all seem to have only the version with one wire. On those you take your two wires from the vehicle and twist them together with the one wire from the switch. Works just fine oddly enough.
