40-2035057 Water pump for G1600 Hercules industrial engines ($200.00 refundable core charge included in price).40 2035057 G1600 Hercules water pump, Caterpillar part number 9Y5969. Gasket included. This part is the same as 40 2035068 and will be item number 1 in the Hercules drawing. Before ordering attention must be paid to the fan adapter, this is the 4 bolt style, there is a 2 bolt style also. The pumps are all the same, part number differences are associated with the fan adapter. Adapters can be easily changed out. Part number for the pump with the 2 bolt