Labrie ALLEY -GATOR RIGHT-HAND, Maintenance Manual

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90 Maintenance
Adjusting Arm Speed
N
OTE
:
No arm speed adjustment is required unless replacing the valve or one of its sections.
Arm speed is controlled by the amount of hydraulic fluid (flow) that is being sent to the arm cylinder.
The arm control valve spools can limit the flow of hydraulic oil, depending on the section of the
valve
1
. Flow is limited by two movement restrictors located on each section.
Figure 3-64 Movement restrictors
To adjust arm speed:
1.
Lock out and tag out the vehicle (see Lockout/Tagout Procedure on page 20).
2.
Secure the area around the path of the arm with barrier tape or barricades.
3.
Put the transmission in Neutral, start the engine, and engage the hydraulic pump.
4.
Clearly identify the stopper screw on the valve that relates to the proper function (boom
extension/retraction, gripper open/close).
5.
Move the lever to evaluate arm speed, then release it.
6.
Loosen the locknut.
7.
Turn the restrictor adjustment screw only one eighth (1/8th) of a turn at a time to clearly feel a
significant change in the arm speed.
8.
Move the lever again to evaluate arm speed. Repeat until cycle times are properly set (see Pressure
and Cycle Time Chart - Body Circuit on page 67).
9.
Tighten back the locknut.
1. Limiting spool strokes limits the quantity of oil (flow) going through them. Controlling the flow of oil means controlling arm speed.
Danger! Do not stand in the path of the arm while carrying out these adjustments.