ARMY TM 9-2805-256-14
AIR FORCE TO 38G2-102-2
NAVY NAVFAC P-8-611-14E
(3) Air supply. The air cleaner, whether oil bath or dry element, cleans the air going to the carburetor. The
oil bath air cleaner uses oil to remove dirt from the air. The dry element air cleaner uses a dry fiber element to
remove dirt from the air. As the element gets dirty, air flow through it decreases and creates a vacuum in the air
cleaner. When air flow decreases too much, the service indicator shows a red signal and indicates the element
(4) Speed regulation. All four models of the engine are equipped with a centrifugal flywheel to the
carburetor by a control rod. The governor determines the fastest speed at which the engine will run. Models
1A08-1 and -2 have no speed regulation other than the adjustment of the governor. Models 1A08-3 and -4 are
equipped with throttle controls which overrides the function of the governor. The throttle control allows the engine
speed to be adjusted between idle and full governed speed.
(5) Ignition system. There are two different types of ignition systems used on the engine. Models 1A08-1,
-2, and -3, all use a breaker point ignition system. A set of breaker points triggers a condenser and coil to produce
a high voltage electric charge. This charge is then delivered, through a shielded high tension cable, to the spark
plug located in the cylinder head. This charge creates a spark at the spark plug electrode, and ignites the air/fuel
mixture in the combustion chamber. Model 1A08-4 uses a breakerless ignition system. This system uses
electronic components to generate the high voltage electric charge to ignite the air/fuel mixture.
(6) Lubrication. Lubrication of the rocker and valve assemblies is accomplished by drawing oil vapors from
the crankcase into the cylinder head assembly. A breather line connects the cylinder head with the air intake
elbow, mounted between the carburetor and air cleaner assembly. On Models 1A08-1, the breather line is
connected directly to the air cleaner assembly. The vacuum in the breather line is sufficient to draw oil vapors
from the crankcase, up through the push rod tubes, and into the cylinder head assembly.