Pulley, Water Pump. PART NO: A-R61436. This water pump pulley is completely new and is used with the RE20022 water pump for the John Deere models shown below. Used w/ A-RE20022 water pump for the below models, (hub must be removed and pulley pressed on in its place). . MODELS: John Deere COTTON PICKER: 9940 John Deere FORAGE HARVESTER: 5720 John Deere FORAGE HARVESTER: 5730 John Deere TRACTOR: 4640 John Deere TRACTOR: 4840.