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 ENGINE LOW IDLE ABNORMAL OPERATION 0009 00 THIS WORK PACKAGE COVERS: Troubleshooting Table and Diagnostic Tests INITIAL SETUP: Tools: General mechanic's tool kit (item 121, WP 0176) Personnel Required Track Vehicle Repairer (2) 63H10 Equipment Conditions: Engine installed in vehicle or ground hop. MALFUNCTION 1: Low idle speed, below 650 rpm. PROBABLE CAUSE CORRECTIVE ACTION a. Insufficient warm-up. Applies in cold weather. (1) Extend warm-up period. Increase warm-up speed to 1000 - 1200 rpm. b. Improper idle adjustment. (1) Adjust idle speed (WP 0043, Throttle Adjustments). c. One bank not firing. (1) Increase warm-up speed to 1000 - 1200 rpm. If bank still does not fire, check fuel- injection pump operation as follows: PROCEDURE OBSERVATION ANALYSIS Remove one engine cover on each side of engine for access to fuel injector nozzle tube fittings. 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. No fuel spray pulsations noted at nozzle fitting. Fuel injection pump deficiency. Replace fuel- injection pump (WP 0115, Fuel Injection Pump Assembly Replacement). Bench Test Install nozzle and holder assembly on tester. Perform nozzle test (WP 0098, Fuel Injector Nozzle and Holder Repair). Spray pattern and nozzle leakage test requirements. If spray pattern is not acceptable and leakage is noted, nozzle is defective. WP 0009 00-1