Engine Systems
Replace the filter as follows:
Fuel Tank
1. Unscrew the filter (or strainer) and discard it.
Refill the fuel tank at the end of each day's operation
to prevent condensation from contaminating the fuel.
2. Fill a new filter replacement cartridge about two-
thirds full with clean' fuel oil. Coat the seal gasket
CAUTION: A galvanized steel tank should never
lightly with clean fuel oil.
be used for fuel storage because the fuel oil
reacts chemically with the zinc coating to form
3. Install the new filter assembly and tighten it to two-
powdery flakes which quickly clog the fuel
thirds of a turn beyond gasket contact.
strainer and filter and damage the fuel pump
4. Start the engine and check for leaks.
and injectors.
AIR SYSTEM
In the scavenging system used in two-cycle engines
and illustrated in Fig. 5, a charge of air, forced into
the cylinders by the blower(s), sweeps all of the
exhaust gases out through the exhaust valve ports,
leaving the cylinders filled with fresh air for
combustion at the end of each upward stroke of the
pistons. This air also helps to cool the internal engine
parts, particularly the exhaust valves. At the beginning
of the compression stroke, each cylinder is filled with
f r e s h , clean air which provides for efficient
combustion.
The blower(s) supplies fresh air required for
combustion and scavenging. The hollow three-lobe
rotors are closely fitted into the blower housing(s)
which is bolted to the cylinder block. The revolving
motion of these rotors pulls fresh air through the air
cleaner or silencer and provides a continuous and
uniform displacement of air in each combustion
Fig. 5 - Air Intake System Through Blower
chamber. The continuous discharge of fresh air from
and Engine
the blower creates a pressure in the air box (air box
pressure).
OIL BATH TYPE AIR CLEANERS
Several types of air cleaners are available for use with
A removable element assembly incorporated in the
heavy-duty oil bath air cleaners removes a major part
the V-71 engines. The light duty oil bath air cleaner
of the dust from the air stream thereby decreasing the
(Fig. 6) is used with some marine models and a light
dust load to the fixed element. An inner cup, which
or heavy duty oil bath air cleaner (Fig. 7) is available
can be removed from the outer oil cup, acts as a baffle
for industrial engines. Some engines are equipped
in directing the oil laden air to the element and also
with a heavy duty dry type air cleaner or a two-stage
controls the amount of oil in circulation and meters
dry type air cleaner (Fig. 8). The air cleaners are
the oil to the element. The oil cup supports the inner
designed for fast, easy disassembly to facilitate
cup, and is a reservoir for oil and a settling chamber
efficient servicing. Maximum protection of the engine
for dirt.
against dust and other forms of air contamination is
possible if the air cleaner is serviced at regular
intervals.
Service the light-duty oil bath air cleaner (Fig. 6) as
follows:
The oil bath air cleaner consists of the body and fixed
filter assembly which filters the air and condenses the
1. Loosen the wing bolt and remove the air cleaner
oil from the air stream so that only dry air enters the
assembly from the air inlet housing. The cleaner may
engine. The condensed oil is returned to the cup where
then be separated into two sections; the upper section
the dirt settles out of the oil and the oil is recirculated.
or body assembly contains the filter element and the
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