Labrie EXPERT, Maintenance Manual, Page: 397 / 425

Lifting Arms
389
Figure 10 - 14 Gripper open (left), closed (right)
How it works:
When the lifting arm is moved up with the gripper open, the limit switch located inside the slide sends
an electrical signal to the solenoid mounted on the valve making the gripper close (works the same as
pressing the gripper-closing button on the joystick). Then, the hydraulic pressure is sent to the
cylinder, closing the gripper before it collides with the hopper walls.
Testing the Auto-Closing System
To test the auto-closing system:
1.
Make sure that the vehicle is parked on safe, level ground.
2. Secure the area around the path of the arm with barrier tape or barricades.
3.
Start the engine and engage the hydraulic pump.
4. If it is not already done, lower and fully open the gripper.
5.
Close the gripper a few inches (away from the arm stowed limit switch) and lift the gripper to see
if it closes automatically.
Warning!
Stay out of the way of the arm while manually moving the H
ELPING
-H
AND
™ lifting arm. Serious
injury or even death may result.
Caution!
Before performing pressure adjustments on the valve, make sure the arm dump valve is
properly set (if adjustable).