Main Control Relief Valve for Kobelco SK230-6E Excavator

The Main Control Relief Valve of the Kobelco SK230-6E excavator is an important component in the hydraulic system.

Basic Information
Applicable Models: Mainly suitable for the Kobelco SK230-6E excavator and also compatible with some other models of excavators, such as Hitachi ZAX330, Hyundai R215-7C, R225-7, and Kobelco SK200-5, SK200-6, SK200-8, SK330LC, SK120-5, etc.

Working principle
The main control relief valve is typically installed on the main oil line of the hydraulic system. When the system pressure exceeds the set value, the relief valve will automatically open, allowing some of the hydraulic oil to flow back to the tank, thereby reducing the system pressure and protecting other components of the hydraulic system from damage due to excessive pressure.

Common Faults and Solutions

Leakage Fault:  This may be caused by seal failure, valve core wear or corrosion. Try cleaning the sealing surface or replacing the sealing ring. If the problem persists, the entire relief valve may need to be replaced.
Unstable Pressure: This is usually due to a loose or damaged adjusting bolt. The adjusting bolt should be adjusted to the correct pressure setting and ensure it is properly tightened.

Slow Response:  This is often caused by valve core damage or dirt blockage. Clean the internal components, especially the valve core, to remove obstructions. If the problem persists, the valve core may need to be replaced.
Inaccurate Pressure Setting: This is often caused by a damaged or loose adjusting bolt. The adjusting bolt should be readjusted to ensure it is correctly set to the desired pressure.