ANTENNA 7Y3990 - Caterpillar

Fuel Filters - Final Fuel Filter
Service the fuel filters at regular intervals determined by fuel conditions.1. Unscrew and remove the filter.2. Clean the gasket sealing surface on the filter base.3. Lubricate the new filter gasket with clean diesel fuel.
Do not pour fuel into the new filter element before installing. Prime the system as instructed in the topic, "To Prime the Fuel System".
4. Tighten the filter by hand until the gasket contacts the base, then tighten 1/2 to 3/4 turn more.5. Turn the fuel supply valve on.6. Start the engine and run at 1000 RPM for several minutes and check for leaks. If the engine fails to start, prime the fuel system. See the topic "To Prime the Fuel System".Primary Filter
1. Stop the engine.2. Shut off the fuel tank supply valve.3. Loosen the nut (1) on the filter cover and lower the filter case (3).4. Remove the element (2) and wash in clean, non-flammable solvent.5. Reinstall the element.To Prime the Fuel System
1. Open the vent valve on the injection pump.2. Unlock the priming pump and operate the priming pump until fuel flows free of air bubbles.3. Close the vent valve and lock the priming pump.