TM 55-1930-209-14&P-1
3-25 Operating instructions.
3-25.1 Operating controls and indicators
3-25.1.1 4.236M diesel engine
3-25.1.1.1 Engine instruments. These are on a small instrument panel on top of the engine block
a.
Engine oil pressure gauge. Located on upper left portion of this small panel, this gauge indicates oil
pressure on its upper scale. Normal oil pressure is 30/60 psi when engine is new at normal operating
temperature and engine is at maximum speed. During the life of the engine, as bearing surfaces wear,
pressure will gradually decrease. When oil is hot or wrong grade of oil is used for certain climatic
conditions, oil pressure may decrease slightly.
b.
Engine coolant temperature gauge. Located on upper right portion of panel, this gauge indicates
temperature of engine block coolant in degrees Fahrenheit on upper scale. A thermostat in the dosed
circuit portion of the cooling system keeps this temperature between 168 and 197F.
c.
Coolant pressure gauge. Located on lower left side of panel, this gauge reads from 0 to 15 psi. Low
pressure is an indication of possibly blocked water passage.
d.
Hour meter. Located on lower right portion of panel, this meter indicates number of hours generator set
has operated and provides the basis for scheduling maintenance and services
3-25.1.1.2 Engine indicators
a
Fuel pressure gauge. On top of fuel oil filtering system, this gauge indicates fuel pressure in psi and
indicates when fuel oil filters should be changed.
b.
Oil dipstick. Located on left side of engine block (looking at engine from generator). The dipstick shows
amount of oil in crankcase. Oil level must be between minimum and maximum marks on dipstick. Never
fill above maximum level.
c.
Coolant filler cap. Located at top front (accessory end) of engine on top of coolant tank. When removed,
cap shows level of coolant in dosed coolant portion of engine cooling system.
3-25.1.1.3 Engine controls
a.
ENGINE CONTROL SWITCH. This switch, on SAG switchboard control panel, has START, REMOTE,
and OFF/RESET positions. To start engine from switchboard, place switch in START. To stop engine
from switchboard, place switch in OFF/RESET. To operate engine from engine, place switch in REMOTE
and use ENGINE START/STOP switch on engine.
b.
VOLTAGE REGULATOR switch. The SAG controls on the switchboard control panel do not include this
switch to control engine speed. It is found on the SSG control panels only.
c.
THROTTLE. Black knob on right side (as you face switchboard) of switchboard housing. Large changes
in speed are obtained by pushing in on center button and then pulling out on throttle knob to increase
speed and pushing in to decrease speed. For fine throttle adjustments, turn knob counterclockwise to
increase speed and clockwise to decrease speed. Most throttle adjustment will be done by turning throttle
knob rather than by pushing or pulling
d.
ENGINE START/STOP switch. Located on engine. Push down on this switch to stop engine regardless of
ENGINE CONTROL SWITCH setting. When ENGINE CONTROL SWITCH switch is in REMOTE, push up
on this switch to start engine.
e.
Red EMERGENCY STOP button on engine control panel. Push to stop engine. When emergency
situation has been corrected, reset by turning clockwise and button will pop out to normal position. Start
engine by following normal starting procedures.
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