As the piston continues on the upward
oil enters a longitudinal oil gallery in the
cylinder block when the supply divides;
stroke, the exhaust valves close and the
charge of fresh air is subjected to com-
a portion entering the by-pass filter, if
pression as shown in Figure 11A-1 (com-
used, and then draining back into the oil
pression).
p a n , part going to the cam and balance
shaft end bearings and cylinder head,
with the remainder going to the main
Shortly before the piston reaches its hi-
bearings and connecting rod bearings via
ghest position, the required amount of
f u e l i s s p r a y e d into the combustion
the drilled crankshaft.
chamber by the unit fuel injector as
Coolant is circulated through the engine
shown i n F i g u r e 1 1 A - 1 o n p a g e 1 1 A - 1
by a centrifugal type water pump. Heat
The intense heat generated
(power).
is removed from the coolant which circu-
during the high compression of the air
lates in a closed system, by the radiator.
ignites the fine fuel spray immediately.
Control of the engine temperature is ac-
The compression continues until the fuel
thermostat
complished by a
which
injected has been burned.
regulates the flow of the coolant within
the cooling system.
The resulting pressure forces the piston
downward on its power stroke.. The ex-
Fuel is drawn from the supply tank
haust valves are again opened when the
through the fuel strainer by a gear type
piston is about half way down, allowing
It is then forced through a
fuel pump.
the burned gases to escape into the ex-
filter and to the injectors. Excess fuel
haust manifold as shown in Figure 11A-1
on page 11A-1 (exhaust). Shortly ther-
is returned to the supply tank through
t h e d o w n w a r d moving
the fuel outlet manifold and connecting
piston
eafter,
lines. Since the fuel is constantly circu-
uncovers the inlet ports and the cylinder
lating through the injectors, it serves to
is again swept with clean scavenging air.
cool the injectors and also carries off any
This entire combustion cycle is completed
air in the fuel system.
in each cylinder for each revolution of
the crankshaft, or in other words, in
Air for scavenging and combustion is
two strokes; hence, it is a "two stroke
supplied by a blower which pumps air in-
cycle".
to the engine cylinders via the air box
and cylinder liner ports. All air enter-
ing the blower first passes through an
GENERAL DESCRIPTION
air cleaner.
The two cycle diesel engine covered in
Engine starting is provided by an elec-
this section is a 4 cylinder model having
starting
system.
The electric
working
parts such
as
trical
major
the
starting motor is energized by a storage
injectors, pistons, connecting rods, cyl-
A battery charging
battery.
inder liners and other parts that are in-
with a suitable voltage regulator, serves
blower,
The
water
terchangeable.
to keep the battery charged.
pump, governor a n d f u e l p u m p f o r m a
group of standard accessories.
Eng i n e s p e e d i s r e g u l a t e d b y a m e c h a n -
ical e n g i n e g o v e r n o r .
Each engine is equipped with an oil cool-
l u b r i c a t i n g oil
filter
fuel
oil
er,
strainer, fuel oil filter, air cleaner, gov-
ENGINE MODEL AND SERIAL NUMBER
ernor, heat exchanger and water pump
and fan, and starting motor.
On all engines, the engine serial number
t h e e n g i n e m o d e l n u m b e r are
and
Full pressure lubrication is supplied to
the cylinder block (see
stamped on
all main, connecting rod camshaft bear-
Figure 11A-2 on page 11A-3). The en-
ings, and to other moving parts within
gine serial number and model number are
the engine. a gear type pump draws oil
also stamped on the option plate attached
from the oil pan through an intake
to the valve rocker cover.
screen, through the oil filter and then to
From the oil cooler, the
the oil cooler.
