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. PROCEDURE OBSERVATION ANALYSIS Solenoid Valve and Fuel Filter: Disconnect one fuel tube from engine front solenoid valve outlet, operate purge pump and press manifold heater switch "ON" and "OFF". With switch in "ON" position, note fuel flow from tee opening with each purge pump stroke. Fuel flow indicates solenoid valve is operating properly and fuel filters are satisfactory. No fuel or restricted flow indicates manifold heater filter or filters in solenoid valve are restricted or clogged. See appropriate vehicle technical manual. If fuel flow stops, solenoid valve is closing properly. With switch in "OFF" position note that fuel flow stops. If fuel flow continues, solenoid valve is defective (stuck open). Replace solenoid. Fine fuel spray pattern indicates proper nozzle operation. Fuel Nozzle Assembly: Disconnect lines and remove nozzle assembly. Reconnect lines to nozzle, (position nozzle beside housing) and operate manifold heater system. With switch in "ON" position, nozzle should have fine conical fuel spray pattern. No spray pattern, stream of fuel, dribble or no fuel indicates defective nozzle or plugged port filters in nozzle assembly. See appropriate vehicle technical manual. WP 0023 00-5