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 FAILS TO START AT NORMAL CRANKING SPEED 0008 00 MALFUNCTION 1: (Continued) Cylinders not firing (insufficient fuel or incomplete combustion). PROCEDURE OBSERVATION ANALYSIS 24 volts at heater switch, both connectors. Proper voltage through heater switch. No voltage to switch. Defective circuit. No voltage from switch. Defective switch. 24 volts at engine bulk head connector. Proper voltage. No voltage to bulkhead connector. Defective circuit between switch and connector. 24 volts at solenoid valve(s) supply and return wire connector. Proper voltage supply to solenoid valves. No voltage at solenoid valves. Defective circuit between connector and valves. 24 volts at ignition unit connector. Proper voltage to ignition unit. (Heater Voltage Checks, Continued) Check electrical circuit voltages (master switch and heater switch "ON"). No voltage at ignition unit. Defective circuit to ignition unit. Ignition Unit Operational Check NOTE Disconnect purge pump fuel hose quick-disconnect coupling at engine before performing test. WARNING High Voltage/High Amperage (see decal on unit) High-tension spark indicates ignition unit operation normal. Remove high-tension wire from igniter (spark plug). Position lead wire end to ground for spark gap (1/4 inch). Note high-tension spark (hot bluish-white) across gap (lead-to- ground). Improper spark or no spark indicates ignition unit or lead is defective Spark Plug Operational Check NOTE Disconnect purge pump fuel hose quick-disconnect coupling at engine before performing test. WARNING High Voltage. High tension spark indicates spark plug firing, operation normal. Remove spark plug, reconnect wire to spark plug, ground plug body to engine and press heater switch "ON". Note high tension spark across spark plug electrodes. No spark indicates the spark plug is defective. WP 0008 00-2