Section VIII. MUFFLER AND MANIFOLD
mounted at the top of the engine and equipped
(1) Remove the muffler (par. 62).
with a weather cap (1). The muffler is con-
(2) Remove the carburetor (par,
nected to the manifold (9) with a pipe nipple
(3) Remove the nuts (7, fig. 17) and lock-
(14) and muffler clamp (3).
washers (8) and flexible hose (6).
b. Manifold. The manifold assembly (9) is
(4) Lift off the manifold assembly (9)
of single casting and is a combination exhaust
from the cylinder block. Remove the
and intake manifold. The manifold is mount-
gaskets (13) and manifold gasket in-
ed on the engine cylinder block and secured
b. Cleaning and inspection.
(1) Clean the manifold with a wire brush
to remove any rust or other foreign
a. Removal Remove the muffler clamp (3)
(2) Examine the manifold for cracks or
and lift off the muffler (2) from the pipe nip-
breaks; replace a defective manifold.
ple (14) on the manifold assembly (9).
(3) Check the manifoId to cylinder block
b. Cleaning and inspection. Inspect the muf-
gaskets and insert. Replace them if
fler for breaks, dents, corrosion, or carbon de-
they were damaged during the re-
posits which may restrict the flow of exhaust
moval of the manifold.
gases. Remove any dirt, carbon, or foreign ma-
c. Installation. Reverse the procedures out-
terial. Replace an unserviceable muffler.
lined in a above. Torque manifold nuts to 40-
c. Installation. Follow the procedures in a
above in the reverse manner.
Section IX. IGNITION SYSTEM
the cylinder head shroud, an intense blue spark
should be observed.
The spark for ignition of the fuel-air mix-
c. Continue the test by inserting the wire in
ture in the cylinders is furnished by a high-
the three remaining terminal posts of the mag-
tension, radioshielded magneto (9), driven by
the timing gears at crankshaft speed. The mag-
d. If no spark is observed, disconnect the
neto distributor plate electrodes are connected
lead wire connecting the magneto to the igni-
to the proper spark plugs according to the en-
tion switch. Retest for spark, and if a spark is
gine firing order (1-3-4-2). At the instant
observed at this point, the ignition switch is at
the distributor rotor electrode makes contact
fault and must be replaced.
with the distributor plate electrode, a surge of
current travels through the spark plug cable (1
e. If no spark is observed in the procedures
to fire the proper cylinder at the correct time.
outlined in a through d above, repair the break-
er points and replace the capacitor in the mag-
65. Ignition Spark Test
neto (par. 66), or replace the magneto as nec-
a. Pull all of the ignition cables out of the
magneto end cover, and insert an insulated
wire, bared at both ends, into one of the termi-
a. General. The
magneto is a four-pole ro-
b. Push the ignition switch in, and crank the
tor, four-pole cam
type, producing four sparks
engine with the starting crank. With the bared
per revolution of
the rotor, which rotates at
end of the wire held one-eight inch away from
In a complete cycle of two