Hydraulic Main Piston Pump 551-1122 551-1136 551-1121 for E330GC Excavator

The K7V160 hydraulic main piston pump is the core power component of the excavator hydraulic system, designed for compatibility with the E330GC model. It supplies pressure oil to drive the boom, arm, bucket, and travel movements with reliable performance.

Manufactured with precise machining processes, this pump delivers stable output pressure and excellent wear resistance, making it an ideal choice for machine overhaul and replacement. It is interchangeable with part numbers 551-1122, 551-1136, and 551-1121.

The following symptoms may indicate that the hydraulic main piston pump requires inspection or replacement:

• Weak digging force and slow working speed
• Abnormal noise and vibration during operation
• Internal wear leading to pressure drop
• Oil leakage at the pump assembly sealing surface
• Unstable hydraulic flow and action jitter

• Verify the machine model before placing an order
• Confirm the part number matches your old pump
• Keep hydraulic oil clean during installation
• Replace the sealing kit together if necessary

Proper verification of model and part number prior to ordering helps ensure correct fitment and avoids unnecessary returns.