Manitowoc Grove GMK 4100L-1, Operating Manual

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Rigging work
12.3 Rigging work after driving with a dolly
Operating manual 3 302 690 en 12 - 21
GMK4100L-1
2
3
.1
1.
201
7
12.3.3
Switching off boom pre-tensioning
You must switch off the boom pre-tensioning before you raise the main
boom off the dolly.
To switch off boom pre-tensioning, you must bring the valves
I
to
IV
into
the required positions, which will empty the pressure accumulator.
•
Switch off the boom floating position;
à
p. 12 - 19.
The valves
II
and
III
are under the pressure
gauge ( 1 ).
•
Open valve
II
– the lever ( 2 ) is vertical.
The pressure accumulator is emptied. The
pressure on the pressure gauge (
1 ) must
drop to 0 bar (0 psi).
The valve
III
stays closed – lever ( 3 ) is horizontal.
S
Danger of the hydraulic oil overheating
Always switch the valve
IV (
à
p. 12 - 19) over (lever in horizontal position)
before operating the crane.
This prevents the pressure in the hydraulic circuit rising and the hydraulic
oil exceeding the permissible temperature of 80 °C (176 °F).