At what PSI will the tractor protection valve control knob pop out?
The tractor protection valve and parking brake valve should close (pop out) on a tractor-trailer combination vehicle and the parking brake valve should close (pop out) on other combination and single vehicle types when the air pressure falls to the manufacturer’s specification (20 – 40 psi).
How do you check a tractor protection valve?
You should test the tractor protection valve by allowing the air supply to properly charge, turning off the engine, then releasing air from the system by pressing the brake pedal several times. The tractor protection valve should move into its emergency position when psi drops to an unsafe level.
What is the purpose of quick-release valve?
The function of a quick-release valve (Fig. 23) is to rapidly exhaust air from the controlled device. It is normally located adjacent to the controlled device, rather than requiring exhaust air to return and exhaust through the control valve. This decreases release time.
What is the yellow knob on a parking brake valve?
The yellow knob is tractor parking brake valve which is also called push/pull or PP valve. The red and yellow knobs share one valve that perform both functions.
Where is the red knob on a tractor?
There is no charge for this service, but standard message and data rates may apply. The red knob is not the tractor protection valve. The tractor protection valve is at the rear of the tractor where the hoses connect to the tractor. The red knob is the trailer charge valve. It’s also called a push/pull or PP valve.
Why is the volume knob on my compressor not working?
The pressure volume knob is not working properly on my compressor. The knob that allows more air pressure popped up and i tried to twist it back on but cant I’m assuming it is stripped because it wont twist back on and i cant take it off. My question is, can i get a replacement knob for it? Or can it be replaced at all?
Do you need to replace the regulator adjusting knob?
Oscar, the knob affects the downstream air pressure, and it is the regulator adjusting knob. If you have stripped it, I suspect you cannot replace the knob and make it work, but you sure can replace the whole regulator. They are not too expensive. You will need to remove the shroud / cover to see how the regulator is plumbed in.