WASHER-HARD 7X0521 - Caterpillar

Fuel Tanks
Condensation can form in partially filled fuel tanks. Top off the fuel tanks after operating the engine.Fuel tanks should have a provision for draining water and sediment from the bottom of the tanks. Some fuel tanks use supply pipes that allow water and sediment to settle below the end of the fuel supply pipe. Drain the water and sediment to help prevent freezing.Fuel Filters
A primary fuel filter and/or a water separator is recommended between the fuel tank and the secondary fuel filter.The micron rating and 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.The micron rating of the primary fuel filter should only be low enough to protect the fuel transfer pump. A primary filter with a low micron rating can be plugged by wax crystals in cold weather.Note: Refer to the Parts Manual for the engine to determine the part numbers of the fuel filters.Fuel Heaters (If applicable)
Fuel heaters help prevent plugging of the fuel filters due to waxing in cold weather. Install fuel heaters so that the fuel is heated before the fuel enters the primary fuel filters.Use a fuel heater that is mechanically simple but adequate for the application. The fuel heater should also prevent the fuel from overheating. High fuel temperatures reduce the performance of the engine. Choose a fuel heater with a surface for heating that is as large as possible but also practical. Small heaters can be too hot because of a limited surface area.For warm weather, disconnect the fuel heater or deactivate the fuel heater. Heat exchanger type fuel heaters should have a bypass provision to prevent the fuel from overheating in warm weather.Only use thermostatically controlled fuel heaters or self-regulated fuel heaters with this engine. A fuel heater that is not thermostatically controlled can heat the fuel above 65 °C (149 °F). A loss of engine power can occur if the fuel supply temperature exceeds 29 °C (85 °F).For further information on fuel heaters, consult your Cat dealer.