20
4.3.6 Rotational Motor
FIGURE 4-3, ROTATIONAL MOTOR & DRIVE CHAIN
The hydraulic torque motor swings the boom left or right by means of a pair of sprockets & roller chain. The motor is
mounted to an adjustment plate located under the chain drive guards. The adjustment plate along with a pair of jack
screws allow for tightening the drive chain. Solenoid valve V-2 controls left/right movement.
4.3.7 Hydraulic Pump
The hydraulic pump is a fixed displacement gear pump, that
produces a flow of 5.6 GPM at 1800 RPM. The probe speed
can be decreased by adding flow controls to any of the
cylinders & actuators, but cannot be increased. Maximum
speeds for troubleshooting are as follows.
Probe Function Approximate Time
IN 2.5 seconds
OUT 4 seconds
UP 8 seconds
DOWN 7 seconds