Multiquip EM98307 Unloader Valve Kit - OEM Replacement Part

The unloader valve kit regulates hydraulic system pressure in Multiquip concrete pumps by diverting oil flow back to tank when the system reaches maximum pressure or during standby operation. This critical component prevents over-pressurization of the hydraulic system and protects pumps, cylinders, and hoses from damage. The unloader solenoid, which this kit services, works in conjunction with the main A and B solenoids to control hydraulic flow during pumping cycles.

In the LS series hydraulic circuit, the unloader valve operates at system pressures up to 4400 PSI, managing flow between the pump, accumulator, and hydraulic cylinders that drive the concrete pistons. When the proximity switches signal cylinder position changes, the unloader valve helps transition pressure smoothly during the shuttle tube motion that alternates between cylinders A and B. Regular inspection and replacement of unloader valve components maintains proper hydraulic system function and prevents loss of pumping pressure or erratic shuttle operation.

This kit is compatible with:

• LS400/LS500
• LS450
• LS600
• LS600P

Genuine Multiquip OEM part, sold by an authorized dealer.