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 7: (Continued) Engine fuel supply pump defective. PROCEDURE OBSERVATION ANALYSIS Fuel Pressure Check Install pressure test gauges: 100 psi gauge in fuel/water separator filter cover bleeder valve opening (WP 0084, Fuel/Water Separator Automatic Drain System and Wiring Harness Replacement). 10 psi gauge in primary filter cover bleeder valve opening (WP 0086, Primary Fuel Filter Repair and Element Replacement). Turn master and in-tank fuel pump switches "ON". Operate engine at high-idle speed (2500-2640 rpm). 40 psi at fuel/water separator filter, and below 1 psi at primary fuel filter. Primary filter restriction. Element dirty or clogged. PROBABLE CAUSE CORRECTIVE ACTION (2) Repair or replace defective fuel pump assembly (refer to pertinent fuel pump manual). a. (Continued) Fuel pump failure (insufficient fuel output due to defective regulating valve, internal pump wear or shaft seal leak causing fuel leakage into engine oil). (3) Drain oil and replace filters in engine (WP 0031, Engine Oil Replacement, and WP 0073, Oil Filters Replacement). MALFUNCTION 8: Fuel injector nozzle defective. PROBABLE CAUSE CORRECTIVE ACTION a. Abnormal spray pattern (sticky action, stuck partially open, or orifices partially plugged). (1) Locate faulty cylinder as follows: PROCEDURE OBSERVATION ANALYSIS Nozzle Malfunction Perform High Pressure Fuel Check on one cylinder at a time with engine idling (all engine covers removed). Note cylinder on which no change in engine operation occurs, or if cylinder misfire still exists. Cylinder is not firing due to defective nozzle. Alternate check with power pack removed. Operate engine at idle speed. Note if cylinder temperature is cold (by touch) at intake port area of cylinder head. A cold cylinder indicates the cylinder is not firing due to defective nozzle. WP 0020 00-9