The Caterpillar 336D excavator is equipped with a hydraulic main pump that has the following specifications:
OEM 2959674
Type: Variable displacement axial piston pump
Maximum flow: 564 L/min (149 gallons/min)
Maximum pressure: 35 MPa (5,076 psi)
Number of pistons: 9
Displacement per revolution: 126 cc (7.7 cubic inches)
Rotation: Clockwise (viewed from shaft end)