712MT OWNER’S MANUAL REVISED 3/4/22 Page 11 of 15
WHEEL DRIVE UNLOADER VALVE
Wheel Drive Unloader Adjustment
The 712MT is equipped with an unloader valve designed to control the wheel speed while the
machine is trenching. This valve is located on the right hand side of the machine behind the
engine.
The valve is preset from the manufacturer. It will most likely need to be fine-tuned in the field
according to the trenching conditions. If the wheels spin excessively, the unloader valve is set
too high. Loosen the lock nut and turn the adjuster screw counter clockwise in small
increments of ¼ to ½ turns. Tighten the lock nut and test trench. Repeat the adjustment if
wheel spin continues to occur.
If the machine progresses too slowly when trenching and the wheels do not spin, the unloader
valve is set too low. Loosen the lock nut and turn the adjuster screw clockwise in small
increments of ¼ to ½ turns. Tighten lock nut and test trench. Repeat adjustment if necessary.
The unloader valve should be adjusted to have minimal wheel spin and the engine is worked,
but not overloaded. Light pressure down on the handlebar will give the wheels more traction.
LOCK NUT
ADJUSTER SCREW
