There are two types fuel filters assembled on Chongqing Cummins diesel generator, light duty and heavy duty fuel filter. The light fuel filter is applied to those engines. Whose power is below 700HP. The heavy duty one is applied to those engines whose power is above 700HP. After the filter have been used for a period of time, the filter will be contaminated and jammed, it must be replaced termly. The interval of the oil and fuel filters can be determined by the consumption curve of the oil and fuel, also, it is recommended that the oil and fuel filter are replaced every 250 hours, 16000 kilometers or 6 months.