Komatsu GD555-5 Operation & Maintenance Manual page 308

MAINTENANCE
ADJUSTING
Adjusting top and bottom position
1. Raise the blade, remove bolts (1) and (5) for clearance (P),
remove circle guides (2) and (6), then adjust the shim
thickness. (Shim thickness: 1 mm (0.039 in), 0.5 mm (0.020
in); 2 types)
SERVICE PROCEDURE
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