NPK DG16 - Troubleshooting Slow Cylinder Speed

38
TROUBLESHOOTING
TROUBLESHOOTING CHART FOR LOW POWER
PROBLEM
CAUSE
CHECK
REMEDY
Operating pressure
is less than 3,625 psi
(250 bar).
Excavator hydraulic
circuit relief valve.
Measure the
excavator circuit
relief valve pressure
with the left hand
shut-off valve
closed.
Adjust or replace the
excavator circuit
relief valve.
Attachment relief
valves.
Measure the
attachment relief
valves with the shut-
off valves open.
Replace the
attachment relief
valve.
Check the relief
valve cartridge for
tightness.
Tighten the relief
valve cartridge.
Check the relief
valve cartridge for
mis-adjustment.
Re-adjust the relief
cartridge.
Check the o-rings
and backup rings of
the relief valve
cartridge.
Replace the o-rings
and backup rings of
the relief valve
cartridge.
Check the seals
between the open
and close passages
of the swivel
manifold assembly.
Replace the seals in
the swivel manifold
assembly.
Check the land
areas for the seals in
the swivel manifold
assembly.
Repair the land
areas or replace the
spindle.
NOTE: If additional assistance is required, call the NPK Service Department at
1-800-225-4379.