Fuel Flow Test (See Fig. 7); Illustrations; Troubleshooting Transformer-Rectifiers (T-Rs) - Hobart 6921 Series Operation And Maintenance Manual

OM-2040 / Operation and Maintenance Manual
90D20 / Generator Sets
f. Fuel Flow Test (see Fig. 7)
Check fuel pump and fuel flow as follows:
(1) Disconnect the fuel return tube at, or near, the tank. Hold the open end in a convenient container
of over 1-gallon capacity.
(2) Start and run the engine at governed speed 2000 RPM. Measure the fuel flow from the return
tube for 1 minute. Flow should be 0.8 gallon (based on 0.080 restriction). If fuel flow is below this
amount, it indicates that the fuel strainer, fuel filter or fuel pump requires servicing or repair.
(3) To check suction side of the pump, immerse the end of the return tube in a container of fuel. If air
bubbles rise to the surface of the fuel, it indicates that air is being drawn into the fuel system on
the suction side of the pump. If air is present, tighten all fuel connections between the fuel tank
and the fuel pump. Check for defective tubes, hoses, etc.

10. Illustrations

Illustrations, Figures 1 through 8, are referred to throughout the Trouble Shooting Chart

11. Troubleshooting Transformer-Rectifiers (T-Rs)

Instructions for troubleshooting and repair of transformer-rectifiers are provided in the appropriate
transformer-rectifier manuals included with Chapter 6 of this manual.
February 28/94 Revised Chapter 3-1
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