TM-9-2320-361-24-1 Field Maintenance Manual Volume 1 for M44A2 Series Trucks
Page 143 of 1176
TM 9-2320-361-24-1 0008 00 0008 00-15 MECHANICAL SYSTEMS TROUBLESHOOTING - DIRECT SUPPORT (Contd) MALFUNCTION TEST OR INSPECTION CORRECTIVE ACTION 1. NO FUEL AT FUEL INJECTORS (Contd) NOTE Air entering fuel delivery lines may block fuel flow. Air can enter lines when fittings are loose or lines or fittings are defective. This is indicated by leaking fuel. 2. Check operation of fuel injector nozzle. Remove fuel injector (WP 0067 00) and bench test fuel injector nozzle (TM 9-2815-210-34-1 and -2). 3. Check fuel delivery lines mounted on, and from, fuel injection pump (WP 0068 00). 4. Check fuel supply pump operation (TM 9-2910-226-34). a. Clean dirt, grease, and paint from fuel delivery line fitting at the final fuel filters, which are mounted in fuel supply pump. b. Operate in-tank fuel pump and crank engine. c. Observe the green port of fuel supply pump. 5. Check fuel injection pump delivery operation. a. Loosen one injector line nut in hydraulic head. b. Operate in-tank fuel pump and crank engine. c. Observe location of loose injector line nut in hydraulic head. 1. If fuel injector nozzle operation is incorrect, clean, adjust, and retest (TM 9-2815-210-34-1 and -2). 2. If fuel injector nozzles are internally defective, replace (WP 0067 00). If fuel delivery lines are leaking or restricted, tighten lines or fittings, repair fuel delivery lines, or replace fittings (WP 0068 00). Bleed air from fuel injection system (WP 0064 00). If no fuel flows from outlet port of fuel supply pump, replace fuel supply pump (TM 9-2910-226-34). If some traces of fuel, or no fuel pressure is evident, replace fuel injection pump (WP 0069 00). Table 2. Fuel System Troubleshooting Procedures (Contd).