Komatsu D31EX-21, Operation & Maintenance Manual, Page: 171 / 256

OPERATION
TROUBLESHOOTING
3-119
OPERATING BRAKE
CAUTION
To operate the brakes, and open the bypass valve and drain all the oil.
The brake system is operated only by opening the bypass valve. If the valve is not at the OPEN position,
the brake pedal and parking lever will not work.
1. After completing the towing operation, cool the pump.
2. Tighten 2 valves (1) used when being towed on the top sur-
face of the pump, then tighten lock nuts (2) and (3) to hold
valve (1) in position.
Tightening torque of valve: 2.5 to 3.5 kgf·m
(24.5 to 34.3 N·m)
Tightening torque of locknut: 2.5 to 3.5 kgf·m
(24.5 to 34.3 N·m)
3. Turn lever (4) of the bypass valve in an upward direction
until it stops (fully open position (A)), then lock lever (4)
with lock pin (5).
4. Remove the quick coupler at port (6) of the bypass valve,
then install the plug and O-ring.
5. Install the floorplate.