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 BACKFLOW VALVE REPLACEMENT 0081 00 THIS WORK PACKAGE COVERS: Test, Removal, Installation INITIAL SETUP: Tools: General mechanic’s tool kit (item 121, WP 0176) Mandatory Replacement Parts: Lock washer (2) (item 92, WP 0175) Expendable and Durable Items: Container for fuel, minimum 1-gallon capacity Personnel Required: Track Vehicle Repairer (1) 63H10 Equipment Conditions: Engine removed from vehicle and placed on a flat stationary surface REMOVAL • To determine if your backflow valve is functioning properly, perform the test in WP 0046. The most notable symptom produced by a non-functioning backflow valve is a non- functioning manifold heater. The fuel backflow valve is a dual purpose valve. 1. It incorporates a check valve that prevents pressurized fuel generated by the purge pump (wobble pump) from back flowing into the primary fuel filter. 2. It incorporates a by-pass valve that limits the fuel pressure to the manifold heaters. The fuel backflow valve is mounted on the damper housing on all 750 horsepower AVDS-1790 engines. There are two mounting configurations, one on the 2CA and 2DA engines and another on the 2DR engine. In addition, the fuel out of the valve fitting is a straight fitting on the 2DR engine. Removal and installation procedures are similar. The two configurations are illustrated below. 2DR Configuration 2CA and 2DA Configuration WP 0081 00-1