- - AGRICULTURE CORE CURRICULUM - - (CLF2000) Advanced Core Cluster: AGRICULTURAL MECHANICS (CLF2800) Unit Title: EQUIPMENT OPERATION AND MAINTENANCE ___________________________________________________________________________ (CLF2804) Topic: FUEL FILTER MAINTENANCE Time Year(s) 1 hour 1 / 2 / 3 / 4 ___________________________________________________________________________ Topic Objectives: Upon completion of this lesson, the students will be able to: Learning Outcome #: (Q-2) - Be able to change fuel filters. (Q-3) - Use safe work habits while servicing, maintaining, and adjusting agricultural equipment. Special Material and Equipment: Gasoline engine; open and box end wrenches; new gaskets; clean rags; solvent; diesel engine; new fuel filters; operator's manual References: Jacobs, C. O., & Harrell, W. R. (1983). AGRICULTURAL POWER AND MACHINERY. New York: McGraw-Hill. Cooper, Elmer L. (1987). AGRICULTURAL MECHANICS: FUNDAMENTALS AND APPLICATIONS. Albany, NY: Delmar Publishers. Resources: Deere & Company. (1984). PREVENTIVE MAINTENANCE (Fundamentals of Machine Operation (FMO) Series). Available from: John Deere Technical Services, Dept. F, John Deere Road, Moline, IL 61265 Evaluation: Quiz by instructor TOPIC PRESENTATION: FUEL FILTER MAINTENANCE A. Importance of Fuel Filter Maintenance 1. The purpose of fuel filters is to remove water, sediment, air bubbles, and abrasive particles from the fuel before it enters the carburetor (gasoline engine) or the fuel injection pump (diesel engine). 2. Air in the fuel lines of a diesel engine can cause the engine to run rough or not start. 3. Water and dirt are the major enemies of a fuel system, especially in diesel engines. a. Water cause parts to rust, and even a very small amount of rust can damage injectors. b. Water interferes with the proper metering of fuel, thereby causing the engine to run rough. c. Dirt and sediment clog fuel lines and grind away the injection pump's fine fitted parts. 3. Refer to the operator's manual of the equipment for the recommended fuel filter service interval. a. A single filter system is usually serviced every 500 hours. b. In a double filter system, the first-stage filter is usually serviced every 500 hours, and the second-stage filter every 1000 hours or each season. B. Gasoline Fuel Filter Maintenance 1. Check for leaks in the carburetor gaskets and the intake manifold connections. a. Start the engine and squirt a few drops of oil over the suspected area. b. If oil is sucked into the manifold connection, tighten the connection and check it again. c. Small engines will reduce rpm's when oil is squirted on an intake leak. 2. Turn off the shut-off valve in the fuel supply line. 3. Take out the fuel strainer without touching the filtering surface and clean it in solvent. 4. If the engine has a disposable fuel filter, fill it with gasoline to see if fuel flows through it rapidly. If it does not, replace it with new filter. 5. Remove and clean the sediment bowl with a solvent-dampened, lint-free cloth. 6. Inspect the fuel tank for proper ventilation; also check to be sure that there is no sediment at the bottom of the tank. a. Open the fuel shut-off valve and observe the fuel flow. b. If the flow is slow, make sure the fuel tank cap ventilation hole is not clogged. c. If the flow is still slow after cleaning the cap, drain the fuel out and clean the fuel lines. d. If sediment is present, completely drain fuel out of tank and flush it with new fuel. e. Do not drain the fuel into a sewer drain, gutter, or on the ground. 7. Reassemble the strainer or filter, the sediment bowl, and the fuel line. 8. Open the fuel shut-off valve, start the engine, and check for fuel leaks. C. Diesel Fuel Filter Maintenance 1. Turn off shut-off valve in the fuel supply line. 2. Clean the outside of the fuel filter and the area around it. 3. If the filter has a drain valve, drain the fuel from it. 4. Remove the filter or the filter bowl. 5. If the filter is not disposable, clean it in solvent. 6. If the filter is damaged in any way, replace it. 7. Clean the inside of the filter bowl or body completely with a lint-free cloth. 8. Install the cleaned filter with a new gasket or a new filter if it is the disposable type. 10. Install the drain plug or turn off the drain valve, and then open the fuel shut-off valve in the supply line. 11. Fill the fuel tank with clean fuel. 12. Bleed the air out of the fuel filters and lines. a. If more than one filter has been serviced, bleed the filter closest to the fuel tank first by opening the bleed valve or plug on the top of the filter. b. If the engine is equipped with a hand pump, pump the handle until the vented fuel is free from air bubbles. c. If a transfer pump is located between the filter and the fuel tank, open the bypass valve to allow the air to bled out of the filter. e. If engine will not start or runs rough, bleed the injection lines. f. Loosen the injection line nuts one turn using two wrenches in order to avoid bending or twisting fuel lines. Be sure to relieve the pressure in the system before disconnecting lines because escaping diesel fuel under pressure can penetrate the skin g. Crank engine until the fuel flowing out of the injection lines is free of foam. h. Tighten the injection line nuts until snug and free of leaks. 18. Wipe the excess fuel off the fuel lines and filters. 19. Start the engine and inspect the fuel system for leaks. _________________________________________________________ ACTIVITY: 1. Service both a gasoline fuel filter and a diesel fuel filter. _________________________________________________________ 6/28/91 OLR/tf #%&C