ENGINE AR-COMPLETE 3494468 - Caterpillar

The fuel flows from the diesel fuel tank through the fuel line, and the primary fuel filter, if the engine is so equipped, to the fuel transfer pump. The fuel transfer pump supplies the fuel under pressure to the fuel filter housing, the filter removes the dirt and other foreign particles. From here the fuel is supplied to the fuel pump manifold for the individual fuel injection pumps. The fuel injection pumps meter and force the fuel through the fuel injection lines and the fuel injection valves in the cylinder head, into the precombustion chamber where it is ignited and passed into the main combustion chamber or cylinder.The primary fuel filter in the fuel system is for the purpose of straining out foreign material from the fuel before it enters the fuel transfer pump.Primary Fuel Filter
Every 50 service hours remove and clean the filter element.To remove the filter element (2), stop the engine and shut off the diesel fuel tank valve. Loosen the nut (1) on the filter cover and lower the filter case (3). Remove the element and wash in clean kerosene or diesel fuel. Reinstall the element.
PRIMARY FUEL FILTER
1-Nut. 2-Filter element. 3-Filter case.Final Fuel Filter
Draining Fuel Filter Housing: Every 50 service hours, or even as often as daily during extremely low temperatures, drain the filter housing of sediment and water which settles to the bottom of the compartment. Close the diesel fuel valve at the fuel tank, remove the filter housing drain plug (2) and open the vent valve (1) in the housing. Replace the drain plug and prime the system. See the topic, PRIMING THE FUEL SYSTEM.
DRAINING FUEL FILTER HOUSING
1-Vent valve. 2-Drain plug. Fuel Filter Elements: The fuel filter elements are of the resin impregnated paper type. When the pleated elements have collected enough contamination to interfere with engine performance, they must be replaced with new elements. These elements will continue to collect particles until fuel will no longer flow through them at a rate to maintain maximum engine performance. They will not discharge their burden into the clean fuel, this is prevented by the fine grade filter paper around the perforated metal core.The resin impregnated paper type filter elements collect and hold contaminants and cannot be washed or otherwise restored.As the filters gradually become clogged with foreign material, the position of the fuel gauge indicator will work back from the original position in the NORMAL (green) range, to the CAUTION (white) range and later into the OUT (red) range. When the indicator shows in the OUT (red) range the filter elements should be changed and new Caterpillar elements installed. Removing Used Filter Elements: To remove the used filter elements, proceed as follows:1. Close the diesel fuel line valve.2. Remove the filter housing drain plug.3. Open the vent in the filter housing.4. Thoroughly clean the top of the cover and around the edges of the gasket joint between the filter housing and cover to prevent dirt dropping into the filter housing when it is