Lesson 3/Learning Event 1
Step 1. Clean the spark plug. If available, use a compressed-air spark plug cleaner. Remove
abrasive material with clean, dry, compressed air.
Step 2. Inspect for excessive burning, pits, cracks, or broken ceramic insulation.
threads for burrs or evidence of having been stripped or cross-threaded.
Test the firing power of the spark plug on a suitable spark plug tester.
Step 4. Measure the electrode gap. It should be 0.028 - 0.033 inch/ 0.071 - 0.083 cm. Use a
leaf or wire gage. Bend the outside electrode until the desired gap is attained.
Inspect the braided cables for broken, torn, or cut strands.
Step 6. Inspect the connector bodies for cracks and breaks. Inspect the springs for broken or
Inspect the connectors for stripped or damaged threads or distorted nuts.
Step 8. Inspect the ignition cable and replace it if it is damaged. Repair or replace spring tips if
required. Replace the rubber insulators around the spring tips if they are torn or damaged.
When installing the spark plug, make certain the gasket is serviceable and
The contact assembly and capacitor are mounted in the accessory case on the governor assembly.
The contact set is connected to a capacitor by a connector. The breaker points are interrupting
devices which break the primary circuit when a high voltage spark is required. The capacitor is
an electrical energy storing device used to minimize arcing during the opening and closing of the
For removal, cleaning, and inspection of the contact and condenser assembly, use the following
Step 1. Unsnap the spring clips and remove the accessory case cover. (Refer to figure 20 on
page 50 to remove the contact assembly and capacitor.)
Remove the two screws which hold the capacitor in place and remove the capacitor.