ARMY TM 9-6115-641-24
AIR FORCE TO 35C2-3-456-12
1-12-1-7. After the generator set engine has been started, the BATTLE SHORT switch can be used to override all of
the potential faults except short circuit.
1-12-2. Fuel System.
1-12-2-1. The Fuel System (Figure 1–3) includes a primary subsystem and an auxiliary subsystem.
1-12-2-2. The primary subsystem consists of fuel lines, fittings, fuel tank, low fuel level float switch, fuel float switch
module, fuel level sender, FUEL LEVEL indicator, fuel transfer pump, fuel filter/water separator, two injection pumps, and
two injectors.
1-12-2-3. Injection pump output is controlled by a mechanical engine governor. The governor also includes a fuel sole-
noid operated shutoff lever which stops operation of the injection pumps when the solenoid is deenergized. With the MAS-
TER SWITCH in the START or either of the two RUN positions, both the fuel solenoid and the fuel transfer pump are ener-
gized. The fuel solenoid positions the shutoff lever to the open position, and the transfer pump starts drawing fuel from
the fuel tank. After reaching the fuel transfer pump, fuel passes through a fuel filte/water separator where water and small
impurities are removed. The fuel then goes to the injection pumps. With the engine cranking or running the fuel is metered,
pressurized and pushed through the injectors by the injection pumps. Fuel is sprayed by the injectors into the engine com-
bustion chamber where it is mixed with air and ignited. The fuel that is not burned by the engine is returned to the fuel
tank by an excess fuel return line. Power is removed from the fuel solenoid and the transfer pump, stopping the engine
whenever the MASTER SWITCH is turned to OFF position. The fuel solenoid and transfer pump are also de-energized
by the fault system (refer to paragraph 1-12-1). The fuel level sender measures tank fuel level which is indicated by the
FUEL LEVEL indicator from E (empty) to F (full).
1-12-2-4. The auxiliary subsystem consists of anauxiliary fuel supply, fuel lines, fittings, auxiliary fuel filter, auxiliary fuel
pump, auxiliary fuel pump float switch located in the fuel tank, and a fuel float switch module.
1-12-2-5. When the MASTER SWITCH is set on PRIME & RUN AUX FUEL, it actuates the auxiliary fuel pump and
transfers fuel from the auxiliary fuel supply to the fuel tank. The auxiliary fuel pump float switch shuts off the auxiliary fuel
pump when the fuel tank is full and reactivates the pump as the level drops. The fuel float switch module allows the current
used by the auxiliary fuel pump to bypass the float switch.
1-12-2-6. The 24 VDC control circuits provide control and power for operation of the fuel solenoid, indicators, fuel trans-
fer pump, and auxiliary fuel pump.
1-10 Change 1
