EKKO EK20R Service Manual page 14

The discharge side of
the pump does not
produce oil
The oil outlet of the oil
pump discharges oil
but the pressure
cannot rise
Low volume efficiency
of oil pump
Oil pump noise
Oil suction side leakage
If not, the pump is damaged
The relief valve is damaged or jammed
by stolen goods, and the oil flows back
to the tank from the relief valve
The side plate of oil pump is seriously
worn and the volume efficiency is too
low
The spool of the relief valve is severely
worn
The overflow valve is jammed by stolen
goods and loosely closed
The pressure regulation of the relief
valve is too low
The oil suction takes in air
The seal inside the oil pump is damaged Replace seal ring
Lateral plate wear
The oil pump contains stolen goods or
too large clearance
The oil pump speed is too low or too
high
Negative pressure in the tank
1. Most cases are caused by insufficient
oil absorption of oil pump, such as oil
absorption filter blockage; Oil level is too
low; Inhalation of air; Suction air at oil
seal, etc
The return pipe is higher than the oil
level, and there are a lot of bubbles in
the oil
The oil viscosity is too high and the oil
temperature is too low
Check the oil absorption part and its
seal, and replace the failed seal
Check and repair pumps or replace
pumps
Check and repair relief valve or
replace relief valve, filter oil or
replace oil
Repair or replace the oil pump
Replace the new cone spool
Filter oil and remove dirt
Adjust the overflow valve to the
specified value
Check whether the sealing ring at
the oil suction port is damaged
Replace the side panel
Remove stolen goods and filter oil;
Replacement of new oil pump
Make the oil pump run within the
specified speed range
Increase the capacity of air filters
Keep oil level high and seal must be
reliable to prevent oil contamination
Immerse the return pipe below the
oil level
Choose oil with proper viscosity
according to the season, or heat it
up
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