Onan CCK Service Manual

Ignition System
GENERAL
These engines use either a magneto ignition system
or a battery ignition system. Each system and the
spark advance mechanism are described in this sec¬
tion. Correct ignition timing is stamped on the crank¬
case near the breaker box (timing procedure given
later). Spark advance is identified by a raised cup¬
shaped cover on the upper rear of the crankcase
below the breaker box. Engines without spark ad¬
vance use a fiat cover which is flush with the crank¬
case. Figure 32 shows magneto ignition while Figure
34 shows the battery ignition system.
MAGNETO
The magneto coil assembly is mounted on theengine
gear cover. The flywheel must be removed to expose
it. The magneto coil assembly has only one set of
mounting holes. Connect the smaller (ground) coil
•pad to the magneto coil assembly mounting screw
hgures 32 and 33. Connect the larger magneto coti
assembly lead to the breaker box insulated terminal
Figure 32. The magneto coil used on engines with
spark advance mechanism includes both the primary
and secondary windings.
FIGURE 32. MAGNETO IGNITION SYSTEM
IF FLYWHEEL RUBS ON POLE SHOE LOOSEN POLE
SHOE MOUNTING SCREWS. TAP POLE SHOE. AND
RETIGHTEN MOUNTING SCREWS.
FIGURE 33. MAGNETO STATOR ASSEMBLY
BREAKER POINTS
To maintain maximum efficiency from the engine,
change the breaker points every 200 hours of opera¬
tion Proceed as follows:
1 Remove the two screws and the cover on the
breaker box.
2 Remove the two spark plugs so engine can be
easily rotated by hand. If plugs have not been
changed within the last 100 hours, replace them
with new ones after setting the breaker points.
3 Remove the two mounting screws (A) and pull the
points out of the box just far enough so screw (B)
can be removed. See Figure 35. Replace points
with a new set but do not completely tighten
mounting screws (A).
4. Rotate the engine clockwise (facing flywheel) by
hand until points are fully open. Turn screw (C)
until point gap measures .020inch (0.51 mm) with
a flat thickness gauge.
5. Tighten mounting screws and recheck gap.
6. Proceed to Ignition Timing.
Each time new breaker points are installed, place a drop of oil
on the point’s pivot point (Figure 35}.
IGNITION TIMING
Ignition Timing — Engine Running: Always check
37

Onan CCK Specifications

General

Cylinders	2
Ignition System	Battery ignition
Fuel Type	Gasoline
Cooling System	Air-cooled
Fuel System	Carburetor
Starter	Electric
Governor	Mechanical
Max RPM	1800 RPM
Engine Type	4-cycle
Bore and Stroke	3.25 x 3.625 inches (82.55 x 92.08 mm)