Doosan DX60R Shop Manual page 83

Hydraulic Cylinder Natural Drop Test
To check boom and arm cylinder tightness against the
specified performance standard for new cylinders, put a full
load of dirt in the bucket and move the attachment cylinders so
the arm cylinder is extended 20 - 50 mm (1" - 2") and boom
cylinders are retracted the same amount, 20 - 50 mm (1" - 2").
The top of the bucket should be approximately 2 m (6' - 7') off
the ground.
Shut down engine and measure cylinder drop after 5 minutes.
Bucket cylinder should not show more than 40 mm (1.57")
change, while the arm and boom cylinders should not fall more
than 10 mm (0.39").
Travel Motor Jack-up Test
Test travel motor operation on each side by painting or chalking
a mark on one crawler shoe, with a corresponding mark on the
travel frame. Use the attachment to jack up one side of the
machine and operate the raised travel motor. Record the
number of seconds it takes the crawler shoe to make 3 full
rotations, during both 1-speed and 2-speed operation.
Operation
1-speed
2-speed
Specification for DX60R
Basic Value
28.36 ± 1.5 sec
16.24 ± 1.0 sec
SP001615
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