FUEL BACKFLOW VALVE REPLACEMENT
THIS WORK PACKAGE COVERS:
Test, Removal, Installation
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
Track Vehicle Repairer (1) 63H10
Engine removed from vehicle and placed on a
flat stationary surface
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
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
Removal and installation procedures are similar.
The two configurations are illustrated
2CA and 2DA Configuration
WP 0081 00-1