PowerBoss Nautilus Hi-Dump PB45HDSL, Service Booklet, Page: 105 / 117

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during scrubbing operations. Just before the hopper lift arm assembly begins to raise, the hopper dump
door automatically closes. If the hopper contents are emptied (by pressing the front of the hopper open
door switch) the hopper door will remain open when lowered. If the hopper is lowered without opening
the hopper door the door will be automatically opened by the tilt switch.
Safety tubes and pins:
The safety pins should always be inserted into the safety tubes when working under or around the
raised bumper or hopper. After raising the bumper and hopper to the desired height remove the pins
from the storage tubes and insert them into the appropriate hole in the safety tubes depending on the
raised height of the bumper and hopper, (low “maintenance” position, medium height position, or fully
raised position).
It is not necessary to “lock” the safety pin in place by lowering the bumper or hopper onto the safety
pin. If however the lift arms are lowered onto the pins relief valves will prevent the cylinders from
causing any damage to the lift arms or adjacent structure.