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 INTAKE MANIFOLD HEATER ABNORMAL OPERATION 0023 00 MALFUNCTION 1: (Continued) Manifold heater inoperative. Ignition Unit Operation NOTE Disconnect purge pump fuel hose quick-disconnect coupling at engine before performing test. WARNING High Voltage! (See decal on unit.) Voltage High Amperage Output. PROCEDURE OBSERVATION ANALYSIS 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 ignition unit lead is defective. Replace unit and lead (WP 0088 Manifold Heater Assembly and Related Parts Replacement). Spark Plug Operation 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 manifold heater switch "ON". Note high-tension spark across spark plug electrodes. No spark, the spark plug is defective. Replace spark plug. Solenoid Valve(s) Operation Evidence of action indicates normal solenoid valve operation. Press manifold heater switch intermittently "ON" and "OFF". Note audible "click" or opening and closing valve action (by touch) of both solenoid valves (fuel supply and fuel return). No audible "click" or action indicates solenoid valve(s) is defective. WP 0023 00-3