Gasoline - Spark Plug & Ignition Coil Testing

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Here we will guide you through testing your Spark Plug and Ignition Coil.

  1. Be sure the on/off switch and fuel is turned on.
  2. Pull over the machine by hand 3 times, or for a short time if it is electric start.
  3. Remove the Boot of the Ignition Coil from the top of the Spark Plug.
  4. Remove the Spark Plug.
  5. Check if the Spark Plug tip is wet with fuel. If not, there is a problem in your fuel system (tank, carb, filter, etc).
  6. Test the Spark Plug to be sure it is firing correctly. This can be done with a Spark Plug Tester or with a multimeter. To test with a multimeter, set your meter at Ohms (10 or 20k) and attach the Red wire to the top of the Spark Plug where you removed the cap. Next, touch the Black wire from the meter to the Spark Plug Electrode (the needle that sits under the metal that curves around the other end of the Spark Plug). A faulty Spark Plug will give a very low reading (0-0.05 Ohms). Replace if faulty.
  7.  If the Spark Plug is working correctly, re-attach it to the Ignition Coil Cap (Boot). Hold the end of the Spark Plug tip to a metal section of the engine, and turn over the engine (you might need a friend to help if your Small Engine Machinery does not have electric start). If all is working correctly, you should see a strong spark.
  8. If you do not get a spark, you next need to check oil level is at the correct level (to the fill level indicated) and repeat step 7.
  9. If you still have no spark, or it stops running within a few minutes of starting, disconnect the oil sensor wire (you will find it on the opposite side to the cylinder side of the engine) and try step 7 again.
  10. Still not getting a spark? Then you need to replace your Ignition Coil (For 2-Strokes – you will need to test the Ignition System further. Please contact us using the form below to submit a support ticket).
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