HPV145 Hydraulic Main Pump Spare Parts 4200227 4179177 8051275 9253685 4366356 2022744 4467592 3106174 Pump Repair Kits

As the key power unit of an excavator’s hydraulic system, the main hydraulic pump is driven by the engine to transform mechanical power into high-pressure hydraulic power. It transports pressurized hydraulic oil to hydraulic motors, facilitating all operational movements of the excavator. The majority of construction excavators adopt axial variable piston pumps. Medium and large excavators are equipped with a combined dual main pump and rear pilot gear pump assembly. Two separate high-pressure oil supply loops feed the main control valve to enable composite working movements, with a rated operating pressure between 28MPa and 35MPa. The low-pressure pilot pump installed at the tail of the machine operates at 3 to 4MPa with a low flow rate, supplying pilot pressure oil for the control joystick and main valve spool actuation. Piston assemblies fixed on the cylinder block and pump housing rotate with the main shaft to finish oil suction and pressurization. Adjusting the inclination angle of the swash plate changes the piston stroke, thereby regulating the pump displacement. An external servo drive controls swash plate motion in response to hydraulic feedback signals. A larger swash plate angle boosts flow volume and operating speed, while a smaller angle cuts fuel consumption and prevents engine stalling. The valve plate separates low-pressure oil intake and high-pressure oil discharge channels to achieve hydraulic oil distribution. Three core control functions guarantee the stable operation of the pump. Constant power control automatically reduces pump displacement under heavy loads to protect the engine and enhance power utilization efficiency. The LS load-sensing system delivers oil flow matching actual working requirements and maintains low idle displacement for fuel economy. The HP pressure limiting function minimizes pump displacement at peak pressure to prevent rupture and damage to hydraulic pipes and oil cylinders. Typical faults include internal leakage caused by piston wear, valve plate fracture or regulator blockage, which results in slow operation and insufficient power output. A stuck maximum-displacement regulator leads to engine overload, black smoke emission and stalling under heavy working conditions. Severe internal leakage converts pressure loss into heat energy, causing abnormal rises in hydraulic oil temperature. Air ingress into the system, low hydraulic oil levels and damaged bearings or pistons will produce abnormal operating noise. Routine maintenance involves regular replacement of hydraulic oil and filter elements to avoid wear of precision internal parts. It is essential to ensure tight sealing of oil suction pipelines to prevent air intake and equipment vibration, and keep hydraulic oil at the standard level to sustain stable pump performance.

Machinery Test Report	Provided	Warranty	3 Months
Video outgoing-inspection	Provided	Brand Name	OEM
Place of Origin	China	Product Name	Hydraulic Pump
Model	HPV145	MOQ	1 Piece
Quality	High-Quality	Delivery time	7-15 Days
Standard or Nonstandard	Standard	Application	Excavator Machinery
Size	Standard Size	Packing	Wooden Box