Labrie Pendpac WITTKE RETRO FL Maintenance Manual page 100

90 Maintenance
Air actuators
Air from the air valves and joystick is routed to the air actuators mounted on the hydraulic valve
sections. The air actuators are dedicated to a particular hydraulic function and influence the direction
in which the valve spool is moved. Once the air supply is removed from the actuator, the valve spool is
centered by its spring, and the actuator returns to the neutral position.
Figure 3-31 Air actuators
Central Air Drain Cocks (optional)
A series of air drain cocks are provided on a bracket at the battery box.
All air tanks should be drained daily.
I :
MPORTANT
N : Be sure to drain the wet tank first.
OTE
Poorly maintained pneumatic control systems are a major cause of packer control failure.
Your air drain cocks may differ slightly from those shown in Figure 3-32.
Figure 3-32 Air drain cocks
Gravity Dump (Tip-to-Dump) Units
Coiled air lines are used to connect the valve box and joystick to the air actuators.
In addition, quick exhaust valves are included in the joystick lines to ensure positive control.