Hyundai HX130LCR Manual page 98

2) MAKE UP VALVE
In the system using this type of motor, there is no counter balance functioning valve and there
happens the case of revolution exceeding hydraulic supply of motor. To prevent the cavitation
caused by insufficient oil flow there is a make up valve to fill up the oil insufficiency.
A make up valve is provided immediately before the port leading to the hydraulic oil tank to secure
feed pressure required when the hydraulic motor makes a pumping action. The boost pressure
acts on the hydraulic motor's feed port via the make up valve.
Pressurized oil into the port B, the motor rotate counterclockwise.
If the plunger of MCV moves neutral position, the oil in the motor is drain via left relief valve, the
drain oil run into motor via right make up valve, which prevent the cavitation of motor.
Relief valve
Make up check valve Make up check valve
A B
140WF2SM04
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