SUPPORT-SUSP 3973104 - Caterpillar

3306, 3306B, 3406 and 3406B Truck EnginesReference: November 1986, Page 4, "Two New Cold Weather Fuel Heaters Available "Caterpillar diesel engines are designed for effective cold weather operation, but how effective your engine operates depends on many factors. Under certain conditions during severe winter weather, an engine fuel heater may be needed to minimize cold weather fuel problems such as plugged fuel filters and fuel tank fittings. If a fuel heater is needed, the Caterpillar 7C3557 Fuel Heater Kit and 7C3558 Heater are recommended. Both offer good protection against cold weather fuel problems without the risk of overheating fuel.
If a fuel heater from another manufacturer is used, some general guidelines should be followed to ensure maximum year-round engine performance. The fuel heater should be installed so that it heats the fuel before the fuel flows through the primary (first) fuel filter. Select a fuel heater that is mechanically simple and adequate for the application. If a heat exchange type fuel heater is used, it should have a bypass provision to prevent overheating the fuel. If possible, disconnect or deactivate the fuel heater during warm weather operation.
Overheating of fuel can result in a loss of engine horsepower. As fuel is heated, it becomes less dense, resulting in lower BTU content (heat) for the same injected volume. Using a standard fuel temperature of29 °C (85°F) at the secondary fuel filter base, engine horsepower will decrease approximately 1% for every 5.6 °C (10°F) increase in fuel temperature. An unregulated fuel heater used during warm weather operation can often raise fuel temperature to in excess of 79 °C (175°F). A fuel temperature of 79°C (175°F) could result in a horsepower loss of nearly 9% which would equal 27 kw (36 hp) for a 298 kw (400 hp) engine.