QUICK RELEASE VALVES AND DIFFERENTIAL QUICK RELEASE VALVEFigure 3 - Midland Differential Quick Release ValveFigure 4 - Quick Release Valve (Basic) (Bendix QR-1)NOTE - In some special applications, a spring and springseat will be found In quick release valves.DIFFERENTIAL QUICK RELEASE VALVEThe differential quick release valve operates identically tothe quick release valve except that the air pressure atthe brake foot valve port (Figure 6) must rise to thepressure level set by the spring in the valve before aircan flow to the brake chamber(s).The air pressure in the brake chamber is always lessthan the pressure in the air line of the foot valve by theamount it takes to operate the differential valve.In IH trucks this valve is found on the CO and COF 9670and 9370 and is mounted on all axles. It is set at 41 kPa(6 psi) + 10 kPa (1-1/2 psi) by the spring selected and isnot adjustable.Figure 5 - Quick Release Valve (Basic) (Midland)Figure 6 - Differential Quick Release Valve (Midland)All of these valves are serviced in the same manner, withsome minor exceptions that are noted.CTS-4079A-CHAPTER V - Page 3
Integrated Publishing, Inc. - A (SDVOSB) Service Disabled Veteran Owned Small Business
