EKKO EK20R Service Manual page 13

Relief valve vibration
Dynamic and noise
There is no self-lock
in forward tilt or the
self-lock in forward tilt
exceeds the standard
(1) Gear pump failure causes and troubleshooting methods
fault
The pump won't take
in the oil
Or oil absorption is
not smooth
Oil pump failure
There is air in the hydraulic system
Pump suction air
Suction pipeline resistance is too large;
The suction side of the oil pump
produces negative pressure
The oil suction filter is blocked
The relief valve has a pressure point
vibration and noise
The oil is not clean, so that the forward
control small spool is stuck
Wrong oil mouth
The oil is not clean, so that the forward
control small spool is stuck
Wrong oil mouth
cause
The oil suction filter has a small flow
area or is blocked by foreign bodies
The liquid level in the tank is low
Oil pump installation position is too high;
Suction range exceeds specified
Oil temperature is too low, oil viscosity is
too high
Suction tubing too thin or too long, too
much resistance
The oil seal of the oil pump is damaged
and air is inhaled
Oil pump rotation is not correct or the
speed is too high
torque
Replace the oil pump
The system will be discharged after
repeated operation for a while
Check oil absorption test of oil pump
Check the cause of negative
pressure
Clean the oil filter and filter the oil
Adjust relief valve, slightly raise or
lower pressure gauge 1 ~ 2 scale
grid
Clean valves, fuel tanks, pipelines,
etc
Switch the wrong oil connection
Clean valves, fuel tanks, pipelines,
etc
Switch the wrong oil connection
Replace the filter with a suitable flow
area or clean the blocked filter
The tank is filled with hydraulic fluid
as required
According to the suction range of the
oil pump, it is within 500mm
Change oil or heat oil seasonally
Change the large diameter tubing,
shorten the length of suction tubing
Replace the new oil seal
Change the oil pump rotation, make
the speed to the specified value
11
maintenance