Komatsu PC78US-6 Operation & Maintenance Manual page 145

OPERATION
MACHINE OPERATIONS AND CONTROLS
Blade During Backhoe Operations
When carrying out deep digging operations with the blade at the
front, be careful not to the boom cylinder hit the blade. Always
position the blade at the back unless it is needed at the front.
Permissible Water Depth
When driving the machine out of water, if the angle of the machine exceeds
15 , the rear of the upper structure will go under water, and water will be
thrown up by the radiator fan. This may cause the fan to break.
Be extremely careful when driving the machine out of water.
Do not immerse the machine in water by more than the permissible
depth (under center of carrier roller (1)).
In addition, for parts that have been immersed in water for a long
time, pump in grease until the old grease comes out from the
bearings. (Around the bucket pins)
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