Komatsu WA180-1 Wheel Loader Service Manual

Table of Contents

• Engine
• Power Train
• Steering System
• Brake System
• Work Equipment System
• Electrical and Electronic System
• Others
• Structure and Functions
• Testing and Adjusting
• Disassembly and Assembly
• Maintenance Standard
• Others

Manual Extract MAIN REGULATOR VALVE:

FUNCTION
• The main regulator valve serves to regulate the oil pressure in the circuit and supply pressurized oil to the clutch and the cut-off valve. The valve also delivers relieved oil to the torque converter and solenoid valve.
OPERATION

• The oil delivered from the pump enters orifice “a”
and reaches the spool rear side through regulator spool (1 ).
• The oil that has reached the spool rear side is pressurized. When the oil is pressurized to the preset pressure, it moves the regulator spool to the left, overcoming the tension of springs (2) and (3). This, in turn, opens the pump A and torque converter B port, allowing the oil to flow into the torque converter circuit.
• If the oil pressure in the circuit goes up, exceeding the set pressure, the regulator spool (1) moves further to the left, causing the pump A and drain C ports to open. Thereby, the abnormally highly pressurized oil relieves itself into the drain opening.