ARMY TM 9-6115-642-24
AIR FORCE TO 35C2-3-455-12
MARINE CORPS TM 09247A/09248A-24/2
1-12.5
Engine Lubrication System.
1-12.5.1
The Engine Lubrication System (FIGURE 1-6) consists of an oil sump, dipstick, pump, oil pressure sender,
OIL PRESSURE indicator, low oil pressure switch, and filter.
1-12.5.2
The oil sump is a reservoir for engine lubricating oil. The dipstick indicates oil level in the sump. The oil level
can only be checked when the engine is not running. The pump draws oil from the sump through a screen removing
large impurities. The oil then passes through a spin-on type filter where small impurities are removed. From the filter,
oil is distributed to the engine’s internal moving parts and then returns to the oil sump. The oil pressure sender located
in the engine crankcase senses oil pressure. The oil pressure is displayed on the OIL PRESSURE indicator. The low
oil pressure switch, also located in the engine crankcase, functions with the generator set fault system. The engine is
automatically shut off if the oil pressure drops below 15 + 3 psi (103.4 + 20.7 kPa).
1-12.6
Engine Air lntake and Exhaust System.
1-12.6.1
The Engine Air Intake and Exhaust System (FIGURE 1-7) consists of an air cleaner assembly, intake man-
ifold, four heater plugs, exhaust manifold, and muffler. The air cleaner assembly includes a dust collector, filter element,
and restriction indicator.
1-12.6.2
Air is drawn into the dust collector and passes through the filter element. Airborne dirt is removed and trapped
in the dust collector and filter element. The restriction indicator indicates when the filter should be serviced. Filtered air
is drawn out of the filter through air intake tubes to the intake manifold where it passes into the engine.
1-12.6.3
The engine exhaust gases are expelled into the exhaust manifold. The exhaust manifold channels the gases
into the muffler that deadens the sound of the exhaust gases. The gases pass from the muffler through the muffler outlet
and are vented upward from the generator set housing. A cover, which is held open by the pressure of the exhaust gases
during operation, closes over the exhaust port to prevent rain, water, or other foreign matter from entering the exhaust
port when the set is not in use. The cover is easily removed for connection of an exhaust pipe for indoor operation.
1-12.6.4
To improve engine starting when ambient temperature is below 40°F (4°C), four heater plugs are located in
the intake manifold. The heater plugs are energized through the preheat relay when the MASTER SWITCH is held in
the PREHEAT position.
1-12.6.5
The DC control circuit provides power to the preheat relay and heater plugs.
1-12.7
Output Supply System.
1-12.7.1
The Output Supply System (FIGURE 1-8) consists of the AC generator, AC voltage reconnection switch,
GROUND FAULT CIRCUIT INTERRUPTER (GFCI), CONVENIENCE RECEPTACLE, current transformer, AC circuit
interrupter relay, load terminals, AC CIRCUIT INTERRUPTER switch, AM-VM transfer switch, AC voltmeter (VOLTS
AC), ammeter (PERCENT RATED CURRENT), frequency transducer, and FREQUENCY meter (HERTZ).
1-12.7.2
Power created by the AC generator is supplied through the current transformer, AC voltage reconnection
switch, and AC circuit interrupter relay to the load terminals. The AC voltage reconnection switch allows configuration
of the generator set for the following voltage connections: 120 volt, single phase, 2 wire; 120/240 volt, single phase, 3
wire; and 120/208 volt, 3-phase, 4wire. The AC generator also provides 120 VAC to the CONVENIENCE RECEPTACLE
through the GROUND FAULT CIRCUIT INTERRUPTER.
1-12.7.3
The AC CIRCUIT INTERRUPTER switch closes and opens the AC circuit interrupter relay. This enables or
interrupts the power flow between the AC voltage reconnection switch and the load terminals. The voltage regulation
system (refer to paragraph 1-12.10) senses generator output voltage and provides a control signal to the generator ex-
citer to maintain the desired generator output voltage. Generator output frequency is controlled by the governor control
system (refer to paragraph 1-12.9), sensed by the frequency transducer and is read on the FREQUENCY meter
(HERTZ). The current transformer provides a reduced current signal to the ammeter (PERCENT RATED CURRENT)
which indicates the percent of rated current being supplied to the load. The position of the AM-VM transfer switch selects
the load terminals from which current and voltage are measured. The AC circuit interrupter relay will open and disconnect
the load whenever an overload or short circuit occurs.
1-12.7.4
The GND (ground terminal) is connected to the generator set skid base. This terminal is also connected to
the ground rod for all generator set operation. The removable link provides a removable, low inductance connection be-
tween LO and GND terminals. This removable link must be in place for all generator set operation except when the load
instructions specifically require its removal.
1-12 Change 2
