Doosan 5001, Instructions Manual

Page: 794 / 810

SP001851 Boom and Arm
Page 12
Park the excavator away from obstructions and all traffic on
clear, flat, level ground. Extend the arm cylinder and crowd the
arm into the boom. Partially retract the boom cylinder so that the
boom is stretched out in front of the excavator, as low to the
ground as possible, with the arm crowded under the boom.
The tip of the arm point should be lowered to secure blocking
that will safely support the weight of the arm. Place the blocking
directly in front of the excavator and make sure that it will not be
unbalanced with an initial weight load that is all to one end,
under the arm point.
Shut off the engine and release hydraulic system pressure -
move any of the control levers with the engine off to release
pressure built up in the accumulator. Manually vent residual
hydraulic pressure in the tank by moving the lever near the cap,
on top of the reservoir.
Before beginning the disassembly of attachment mounting pins,
disconnect the arm cylinder hydraulic hose couplings and put a
clean plug in the end of each one. Use any and all reasonable
precautions necessary to avoid introducing dirt or other
contaminants into the hydraulic system. Wipe down coupling
points before disconnecting hydraulic lines and use evaporative
type solvent spray cleaner. Tag and mark hoses for reassembly,
if necessary.
Place a sling under the arm cylinder (the cylinder used to extend
and retract the attachment arm, pinned to the top of the boom).
Lift the sling so that the weight load on the rod end of the arm
cylinder (pinned to the ears on the inner end of the arm) is
released. Prepare blocking under the arm that will securely
support the weight of the arm and arm cylinder.
WARNING
Secure the swing lock and tag and lock out controls in the
operator's cabin to keep anyone from moving or
inadvertently starting the engine. Restrict access to the
work site while sections of the attachment are in the air, or
while they are being supported by the assist crane. The safe
lifting capacity of the assist crane or hoist that is used must
exceed the weight of the heaviest section of the attachment,
the boom (approximately 2,000 kg [4,400 lb], not including
the weight of accessories or fixtures).