FUEL PUMP TESTING AND CALIBRATION (Contd)
d. Fuel Pump Run-in (Big Cam I and Big Cam III)
The test stand motor switch (22) is marked "REVERSE" and "FORWARD." For all testing
of this pump, the test stand motor switch (22) must be set to the "REVERSE" position.
This position corresponds to the right-hand drive rotation requirements for this fuel
pump. If the motor switch (22) is in the incorrect position, the pump will run dry and
could be damaged.
Be certain the fuel filter screen (46) is clean and installed correctly. Foreign material in
the pump could damage seals, gears, or shafts, and plug up the fuel passages. Check
to see that the fuel filter screen (46) is installed with the hole in the screen at the
bottom. If the fuel filter screen (46) is installed upside down, it will cut off all fuel flow to
the pump. The pump will then run dry and could be damaged.
For a complete description and location of the test stand controls, refer to
TM 9-4910-387-14&P, Tester, Fuel Injection, Single End Drive, 150 to 3000 RPM.