DIY Lawn Mower Ignition Coil Test: Save Time and Money

If your lawn mower is experiencing ignition problems, the ignition coil may be the culprit. Testing the ignition coil is a crucial step in diagnosing and resolving ignition issues. This comprehensive guide will provide you with step-by-step instructions on how to test an ignition coil on a lawn mower, helping you get your mower back in working order.

Understanding the Ignition Coil

The ignition coil is a vital component in the ignition system of a lawn mower. It converts the low voltage from the battery into a high voltage that is necessary to create a spark at the spark plug. This spark ignites the air-fuel mixture in the combustion chamber, starting the engine.

Tools and Materials Required

• Multimeter
• Spark plug wrench
• Screwdriver
• Gloves

Safety Precautions

• Always wear gloves when handling electrical components.
• Disconnect the spark plug wire before performing any tests.
• Keep the lawn mower in a well-ventilated area.

Step-by-Step Testing Procedure

1. Disconnect the Spark Plug Wire

• Locate the spark plug wire and remove it from the spark plug using a spark plug wrench.

2. Set Multimeter to Resistance Function

• Set the multimeter to the ohms or resistance function. The resistance range should be between 0 and 2,000 ohms.

3. Test Primary Resistance

• Connect one probe of the multimeter to the positive terminal of the ignition coil and the other probe to the negative terminal.
• The resistance reading should be between 0.5 and 2 ohms.

4. Test Secondary Resistance

• Disconnect the ignition coil from the spark plug wire.
• Connect one probe of the multimeter to the output terminal of the ignition coil and the other probe to the metal ferrule on the spark plug wire.
• The resistance reading should be between 5,000 and 10,000 ohms.

5. Check for Continuity

• Set the multimeter to the continuity function.
• Connect one probe of the multimeter to the positive terminal of the ignition coil and the other probe to the negative terminal.
• The multimeter should emit a beep, indicating that there is continuity.

6. Check for Grounding

• Set the multimeter to the continuity function.
• Connect one probe of the multimeter to the negative terminal of the ignition coil and the other probe to a metal surface on the lawn mower.
• The multimeter should not emit a beep, indicating that there is no grounding.

Interpreting the Results

• Primary Resistance: If the primary resistance is outside the specified range, the ignition coil may have a faulty primary winding.
• Secondary Resistance: If the secondary resistance is outside the specified range, the ignition coil may have a faulty secondary winding.
• Continuity: If there is no continuity in either the primary or secondary winding, the ignition coil may have a broken wire or a faulty connection.
• Grounding: If there is grounding in the ignition coil, it may have a short circuit or a damaged insulation.

Troubleshooting and Repair

If the ignition coil fails any of the tests, it may need to be replaced. Here are some common troubleshooting tips:

• Check for loose or damaged connections.
• Clean any corrosion or debris from the ignition coil terminals.
• Replace the spark plug if it is worn or damaged.
• Consider replacing the ignition coil if all other troubleshooting measures fail.

Conclusion

Testing the ignition coil on a lawn mower is a straightforward process that can help you diagnose and resolve ignition problems. By following the steps outlined in this guide, you can determine if the ignition coil is faulty and take appropriate repair or replacement measures to get your lawn mower running smoothly again.

FAQ

1. Why is my lawn mower not sparking?

• The ignition coil may be faulty.
• The spark plug may be worn or damaged.
• There may be a loose or damaged connection in the ignition system.

2. How often should I test the ignition coil?

• It is recommended to test the ignition coil annually or as needed if you experience ignition problems.

3. Can I repair the ignition coil myself?

• It is possible to repair the ignition coil if you have the necessary tools and experience. However, it is generally recommended to replace the ignition coil if it is faulty.