PIPE ASSEM. 7S5449 - Caterpillar

Industrial And On-Highway Truck EnginesDuring operation in cold temperature conditions, some customers have had fuel filter problems in areas where lighter grade fuels are not easily available. Heavier grade fuels have a higher "cloud point", which is the temperature where wax becomes solid particles in the fuel. When atmospheric temperatures are lower than the "cloud point" of the fuel, the solid particles of wax fill the fuel filters and stop the flow of fuel. To prevent this problem, a new 8N9754 Fuel heater Changeover Group is now available for field installation. The new fuel heater uses engine coolant to heat the fuel and prevent the development of solid wax particles. The heater is mounted separately and connected into the fuel supply line to the fuel filter. A Special Instruction, Form SEHS7653 is sent with each group for installation.
When a fuel heater is used, and atmospheric temperatures are below approximately 32°F (0°C), the recommendation is to start the engine and run it at low idle rpm until the coolant hoses to the heater become warm. This will keep the amount of wax in the fuel filter at a minimum.