Onan CCK - Engine Tune-Up Components

SPARK PLUGS
Replace spark plugs every 100 hours or at least once a
year. A badly leaded plug will cause misfiring, poor
operation or stopping when a load is applied.
• Black deposits indicate a rich mixture.
• Wet plug indicates misfiring.
• Badly or frequently fouled plug indicates the need
for a major tune-up.
Each time the spark plugs are removed, inspect, clean
and regap (Figure 10). If the plug looks discolored or
has fouled, replace it.
GOVERNOR LINKAGE
The linkage must be able to move freely through its
entire travel. Every 50 hours of operation, clean the
joints and lubricate as shown in Figure 11. Also
inspect the linkage for binding, excessive slack and
wear.
CRANKCASE BREATHER
Lift off the rubber breather cap and carefully pry valve
from cap (Figure 12). Wash and rinse the whole valve
in a suitable solvent. Dry the valve and re-insert. Be
sure the valve flapper is toward the engine.
FIGURE 12. CRANKCASE BREATHER
SPEED BOOSTER (5.0 CCK Only)
Use a fine wire to clean the small hole in the short
vacuum tube which fits into the hole in the top of the
engine intake manifold. Do not enlarge this hole. If
there is tension on the external spring when the unit is
operating at no load or light load, it may be due to
improper adjustment, restricted hole in the small
vacuum tube, or a leak in the booster diaphragm or
gasket.
CLEAN
FIGURE 11. GOVERNOR LINKAGE
FIGURE 13. VACUUM SPEED BOOSTER