TM-9-2320-361-24-1 Field Maintenance Manual Volume 1 for M44A2 Series Trucks
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TM 9-2320-361-24-1 0006 00 0006 00-3 MECHANICAL SYSTEMS TROUBLESHOOTING - UNIT (Contd) MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 2. ENGINE CRANKS BUT WILL NOT START (Contd) 4. Check in-tank pump pressure (WP 0061 00). 5. Turn accessory switch to ON position and check pressure at secondary and final fuel filters (WP 0064 00). 6. Check fuel tank pickup tube for restrictions (WP 0061 00). 7. Check fuel pump for proper fuel pressure (WP 0061 00). 8. Check fuel shutoff for proper adjustment (WP 0071 00). If pressure is below 4 psi (27.58 kPa) replace in-tank fuel pump (WP 0061 00). 1. If pressure is below 2 psi (14.0 kPa), remove and replace primary fuel filter (WP 0063 00), and recheck pressure at secondary and final fuel filters. If pressure is still below 2 psi (14.0 kPa), replace secondary and final fuel filters (WP 0064 00). 2. If filters are clean and pressure is still below 2 psi (14.0 kPa) at secondary and final fuel filter, inspect fuel lines for kinks, bends, breaks, loose connections, restrictions, and leaks. Repair fuel lines if damaged. Remove restrictions from fuel tank pickup tube (WP 0061 00). 1. If fuel pressure gauge reads no pressure, inspect electrical connections. 2. If electrical connections are properly connected, replace fuel pump (WP 0061 00). Adjust fuel shutoff for proper operating conditions (WP 0071 00). 3. STARTER CRANKS ENGINE SLOWLY 1. Check starting system circuits (WP 0012 00, table 2, malfunction 2). 2. In cold weather, make sure proper engine oil is being used and/or replace oil (WP 0020 00). 3. Check water pump and belt-driven accessories. Remove all belts (WP 0084 00 and WP 0182 00). Manually turn drive pulley of each accessory and water pump If starting system circuits are damaged, repair or replace. Use proper engine oil for climate conditions. 1. If water pump drive pulley will not turn, replace water pump (WP 0082 00). 2. If any drive pulley accessory will not turn, replace accessory (WP 0085 00, and WP 0180 00). 4. ENGINE STOPS DURING NORMAL OPERATION 1. Check air cleaner for restrictions (WP 0006 00, table 1, malfunction 1). 2. Check fuel system for contamination and restrictions (WP 0006 00, table 1, malfunction 2). 3. Check for restrictions in exhaust system. Ensure exhaust system is not bent, restricted, or damaged. Remove restrictions from air cleaner. If water or contamination is present, remove fuel tank (WP 0060 00). If exhaust system is damaged or restricted, replace damaged parts (WP 0073 00). (For M50A3 series vehicles, refer to WP 0074 00). Table 1. Engine Troubleshooting Procedures (Contd).