Advertisement
4.2 LOSS OF DRIVE
The rubber track systems are driven using hydraulic motors connected to planetary drive
gearboxes. The hydraulic motors are driven using the hydraulics fitted to the machine.
Begin by making a visual inspection of the tracks, particularly around the sprocket, idler and
bottom rollers where material / objects can sometimes lodge. Follow this by inspecting all hoses
and connections, ensuring there are no leaks or blocks. If there are no physical impedances in
the tracks and no faults are found with hoses and connectors, please read below checks that
can be made and possible causes:
Check 1:
Using pressure / flow testing equipment, measure the values of flow and pressure being
applied to the hydraulic motors.
Possible Cause:
If the values of flow and pressure passing to the hydraulic motors is less than that required
to drive the tracks (see machine manufacturer's separate publication), there may be a fault
in the machine hydraulic system.
Check 2:
Test the hydraulic pressure being applied to the brake release port on the gearbox. In order
to release the brake, this should be fed with a pressure of between 12 and 50 bar.
Possible Cause:
If the pressure is below 12 bar, do not attempt to drive the tracks. With a pressure below 12
bar, the brake will not release when attempting to drive the tracks. This can cause the
brakes to seize requiring a replacement unit to be fitted.
Check 3:
If a valve is fitted to the hydraulic motor flange, ensure there are no visible faults with the
valve, and none of the connections are damaged / leaking.
Possible Cause:
If there are no visual faults with the valve, and all other checks fail to identify any faults, the
valve block may need replacing.
19
Advertisement
