ARMY TM 9-6115-641-24
AIR FORCE TO 35C2-3-456-12
1-12-3. Generator Set Cooling System.
1-12-3-1. The Generator Set Cooling System (Figure 1-4) includes air intake and exhaust grilles, baffles, and ducting
within the generator set housing and the engine driven radiator cooling fan. The air intake grilles are Iocated in panels on
both sides of the generator set housing. The air exhaust grille is located in the housing top panel.
1-12-3-2. Air is drawn in through the air intake grilles and forced through the engine coolant radiator and outof the gener-
ator set through the exhaust grille by the radiator cooling fan. Some of the air drawn into the housing is used by the Engine
Intake and Exhaust System (refer to paragraph 1-12-6). Most of the cooling airflows externally past the generator assem-
bly and engine, Some cooling air is circulated internally through the AC generator assembly by a generator fan which is
an integral part of the AC generator assembly. Baffles, ducting, and sound absorbing material are used to control the air
flow through the generator set and to reduce sound transmission through the grilles
1-1241. The Engine Coding System (Figure 1-5) consists of a radiator, hoses, thermostat, temperature sender, cool-
ant high temperature switch, COOLANT TEMP. indicator, water pump, a belt driven fan, and cooling jackets (part of en-
1-1242. The water pump forces coolant through passages (cooling jackets) in the engine block and cylinder head
where the coolant absorbs heat from the engine. When the engine reaches normal operating temperature, the thermostat
opens and the heated coolant flows through the upper radiator hose assembly into the radiator. The cooling fan circulates
air through the radiator where the coolant temperature is reduced.
1-12-4-3. A coolant high temperature switch in conjunction with the fault system provides automatic shutdown in the
event that coolant temperature exceeds 225 ± 5°F (107 ± 3°F). The COOLANT TEMP. indicator indicates the engine cool-
ant temperature, from 120°F to 240°F (48°C to 115°C).
1-12-5. Engine Lubrcation Svsterm.
1-12-5-1. The Engine Lubrication System (Figure l-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 dis-
tributed to the engines internal moving parts and then retums 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 Iow oil pressure switch,
also located in the engine crankcase, functions with the generator set fault system. The engine is automatcally shut off
if the oil pressure drops below 15 ± 3 psi (103.4 ± 20.7 kPa).
1-12-4. Engine Cooling System.