Pump drive coupling 4464407 excavator, aftermarket

For the excavators: pump drive coupling 4464407, an aftermarket part.

On excavators the hydraulic pump is coupled directly to the engine flywheel, and the drive coupling is the only flexible part of that connection. Its elastic elements smooth out the torque pulses from every firing stroke, so the pump shaft, bearings and splines are spared from shock. Coupling size is set by the torque to be carried and the flywheel flange size, so the coupling is chosen by part number and the diameter and spacing of its bolt holes are compared with the old one. Knocking from the pump side with the engine running, especially at idle and when the engine stops, shows that the elements are worn. If the coupling breaks, the pump stops and the machine loses all its hydraulics, so replace the coupling without delay once wear shows.

Specifications

Compatibility

Other parts are in Hydraulic pumps.

Fitting

To change the coupling, separate the pump or engine side and clean the flywheel flange and pump shaft. Tighten the new coupling bolts to the specified torque in a cross pattern and grease the splines as the manufacturer recommends. After assembly, run the engine at idle and listen for knocking and vibration.