MAINTENANCE OF M939 SERIES VEHICLES - OD1661 - LESSON 1/TASK 1
MEDIUM WRECKER - CONTROLS
(5) Trailer Service Air Coupling, is connected by an air coupling
hose to the service coupling of a trailer or vehicle to be towed.
This connection permits the operator to engage the brakes of the
towed load when pressing the brake pedal of the towing vehicle.
(6) Directional Control Lever (figure 13 on the following page),
controls the rotation of the rear winch drum. This control is pulled
back to WIND and pushed forward to UNWIND.
The center position is
(7) Torque Control Lever, is pushed forward to HIGH for heavy
winch loads and pulled back to LOW for light winch loads. The lever
must be engaged in HIGH or LOW before operation of the directional