Komatsu PC18MR-3 Operation & Maintenance Manual page 78

OPERATION OPERATION
10. Turn until the stopper hook at the top of lock pin (10) catches
securely on pin (12) in the insertion portion.
NOTICE
Check that lock pin (10) is hooked to pin (12) and does not come out.
This completes the 2nd stage lock, and and the operation to
open the floor is completed.
DETAILED CONTROLS AND GAUGES DETAILED CONTROLS AND GAUGES
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