Excelsior-HENDERSON HCX 1999, Service Handbook

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6999-0003 7/15/99
ENGINE CONTROL SYSTEM
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5. Remove the ignition coil from the spark plug by pulling up
on the coil.
6. Disconnect the wiring harness from the ignition coil.
Press the connector release tab down and remove the
connector.
7. To prevent debris from entering the engine through the
spark plug hole, use pressurized air to blow clean the area
around each spark plug.
WARNING
Wear face protection since low-pressure air can blow
debris into your eyes and face.
8. Remove the spark plug from the cylinder head.
INSPECTION
SPARK PLUGS
Replace spark plugs every 10,000 miles. Both spark plugs
should have light or medium tan color deposits on the
insulator around the electrode tip.
The spark plug electrode tip and bridge should have sharp,
square edges. Damaged electrodes can indicate engine
problems.
• Sooty black deposits indicate rich fueling conditions. This
may be caused by an obstructed air intake or leaking
injectors.
• Light brown, glassy deposits indicate lean fueling
conditions. This may be caused by low fuel pressure,
plugged or faulty fuel injectors, or intake air leakage.
• Wet, black deposits indicate oil fouling. This may be caused
by worn pistons and piston rings, loose valves, or worn
seals.
Use a wire brush to clean the electrode and tip of a
serviceable spark plug. Inspect the spark plug gap. If the
value is not in range, set the gap with a feeler gauge.
Standard: 0.035 inches