How To Lower Work Equipment When Engine Stops Due To Abnormality - Komatsu PC78US-6 Operation & Maintenance Manual

TROUBLES AND ACTIONS

HOW TO LOWER WORK EQUIPMENT WHEN ENGINE STOPS DUE TO ABNORMALITY

Before loosening the plug, thoroughly check safety under the work equipment and the blade.
Never allow anyone to go under the work equipment or the blade.
While the work equipment is descending, keep holding the plug with a tool, so that the descent may be stopped any moment.
Should it become impossible to lower the work equipment, take the following actions.
1. Open the dust cover.
NOTICE
Do not loosen the plug by more than 5 turns. Otherwise the plug goes off
and the hydraulic oil will spurt out.
2. Loosen plug (1) of the main valve slowly to lower the work
equipment. Loosen the plug by approx. 3.5 to 4 turns .
3. When the work equipment is lowered on the ground, tighten
plug (2).
Tightening torque: 34 to 44 N m (3.5 to 4.5 kgf m, 25.3 to 32.5
lbft)
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OPERATION