64 SEBU8726-03 Operation Section Fuel Related Components in Cold Weather The location of a primary fuel filter is important in cold weather operation. The primary fuel filter and the fuel supply line are the most common components that are affected by cold fuel. Fuel Heaters Note: The OEM may equip the application with fuel heaters. If this is the case, the temperature of the fuel must not exceed 73 °C (163 °F) at the fuel transfer pump. For more information about fuel heaters (if equipped), refer to the OEM information.