Excavator Main Pump

The excavator main pump (also called the hydraulic main pump) is the core component of an excavator's hydraulic system, responsible for converting mechanical energy from the engine into hydraulic pressure to power the machine's movements (e.g., boom, arm, bucket, and swing).

1. Types of Excavator Main Pumps

Most modern excavators use variable displacement axial piston pumps due to their efficiency and controllability. Common types include

Swashplate Piston Pumps (e.g., Kawasaki K3V, K5V  Bosch Rexroth A10VO, A11VO)

Bent Axis Piston Pumps (less common in excavators) 

Load-Sensing Pumps (automatically adjust flow based on demand)

Some older or smaller machines may use gear pumps, but these are less efficient for high-power applications.

2. Key Features & Specifications

Parameter Typical Range

Displacement 20cc – 250ccrev (varies by excavator size)

Max Pressure 300 – 400 bar (30 – 40 MPa)

Control Type Load-sensing (LS), Pressure Compensated (PC), or Electro-Hydraulic (EH)

Drive Connection Spline or flange-mounted to the engine

3. Common Brands & Manufacturers

Kawasaki (Japan) – K3V, K5V series (used in Hitachi, Caterpillar, etc.)

Bosch Rexroth (Germany) – A10VO, A11VO series (common in Volvo, Liebherr) 

Danfoss (Denmark) – 90-series pumps 

Doosan (South Korea) – DP series 

ELEPHANT FLUID POWER (China) – Cost-effective alternatives to major brands

4. Common Failure Symptoms

Low hydraulic pressure → Weak digging force

Overheating → Fluid contamination or internal leakage 

Loud noisevibration → Cavitation or bearing failure 

Slow operation → Worn pistonsswashplate

5. Maintenance & Replacement Tips

✔ Check hydraulic fluid regularly (contamination is a major cause of pump failure).

✔ Monitor pressure & flow with diagnostic tools.

✔ Use OEM or high-quality aftermarket pumps for longevity.

✔ Ensure proper alignment when installing a new pump.

Would you like details on a specific pump model or troubleshooting steps

www.heavyequipmentmaintain.com

excavator hydraulic pump

excavator hydraulic pump price

excavator hydraulic pump repair

excavator hydraulic pump parts

excavator hydraulic pump diagram

excavator hydraulic pump pressure

excavator hydraulic pump working principle

excavator hydraulic pump adjustment

excavator hydraulic pump regulator

excavator hydraulic pump rebuild

mini excavator hydraulic pump

chinese mini excavator hydraulic pump

cat excavator hydraulic pump

hitachi excavator hydraulic pump

chinese mini excavator hydraulic pump upgrade

kobelco excavator hydraulic pump

doosan excavator hydraulic pump

how does an excavator hydraulic pump work

chinese excavator hydraulic pump

mini excavator hydraulic pump upgrade

excavator main hydraulic pump

excavator machine hydraulic pump

excavator main pump diagram

excavator main pump parts

excavator main.pump pressure

excavator main pump regulator

excavator main pump coupling

hydraulic main pump excavator

main pump excavator hitachi

 888 excavator main hydraulic pump

excavator hydraulic main pump parts

excavator hydraulic main pump