TM-9-2815-220-24 Maintenance Manual for AVDS-1790-2CA AVDS-1790-DA and AVDS-1790-2DR Engines Download
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TM 9-2815-220-24 FUEL SYSTEM ABNORMAL CONDITIONS 0020 00 MALFUNCTION 8: (Continued) Fuel injector nozzle defective. PROCEDURE OBSERVATION ANALYSIS High Pressure Fuel Check • Keep hands away from nozzle during test. Remove one engine cover on each side of engine for access to fuel injector nozzle tube fittings (WP 0072, Engine and Transmission Oil Cooler Access Covers and Frames Replacement). Crank engine with fuel switch "ON" or start engine and operate at idle speed. High-pressure fuel spray pulsations at nozzle fitting. Fuel injection pump action is normal. Loosen fuel injector tube fitting at nozzle end sufficiently to allow fuel leakage (one nozzle on each side of the engine). NOTE Leave fitting loosened only long enough to verify fuel is flowing. No fuel spray pulsations noted at nozzle fitting. Fuel injection pump deficiency. NOTE Test all fuel injector nozzles for proper operation after a fuel injection pump failure. Bench Test Install nozzle and holder assembly on tester. Perform nozzle test (WP 0098, Fuel Injector Tubes, Brackets, and Associated Parts Replacement). Spray pattern and nozzle leakage test requirements. If spray pattern is not acceptable or leakage is noted, nozzle is defective. Nozzle Loose in Cylinder Operate engine at idle speed. Note any movement (jumping) of nozzle in cylinder head (visually or by touch). Movement indicates loose nozzle cap nut in body, or collapsed nozzle holder spring. Nozzle is defective. PROBABLE CAUSE CORRECTIVE ACTION a. (Continued) Abnormal spray pattern (sticky action, stuck partially open, or orifices partially plugged). (2) Repair or replace defective nozzle assembly (WP 0114, Fuel Injector Nozzle Replace/Repair). WP 0020 00-10