PISTON MOTOR 9X1518 - Caterpillar

To prevent possible personal injury, make sure the pressure in the system is zero before any air lines are disconnected.
4. Disconnect air lines (1), (3), (4) and (5) from pressure protection valve (2).5. Remove the nuts that hold valve (2) in position, and remove the valve. The following steps are for installation of the pressure protection valve.6. Put pressure protection valve (2) in position, and install the bolts that hold it in place. Air line (1) is from the horn valve. Air line (3) is from the governor air reservoir. Air line (4) is from the windshield wiper valve. Air line (5) is from the brake release air reservoir.7. Connect hoses (1), (3), (4) and (5) to pressure protection valve (2).8. Install the seal and cover assembly on the rear of the cab.9. Remove the body retaining cable, and lower the truck body.