How to check a spark plug gap on a petrol product
The spark plug gap is an air gap between the ground electrode and the centre electrode.
If the gap is too small, the spark struggles to ignite the fuel and air mixture. If the gap is too large, it can make it difficult for the spark to bridge the gap.
Over time, the electrodes wear away due to the constant arcing of sparks.
This can lead to the gap becoming larger and might result in difficulties with starting your chainsaw.
Measuring the spark plug gap
To measure the spark plug gap you can use:
- A feeler gauge
- A coin
- A wire
- A blade
Use the tool to measure the gap by sliding it between the electrode tips.
Place the correct blade or wire from your gap tool between the tips of the electrode, or use a coin to find the measurement.
Be careful not to touch centre electrode, as damaging it will require you to replace the spark plug.
Checking if the spark plug gap needs adjusting
If the tool goes through the gap without touching the electrodes, the gap is too wide.
If the tool does not fit through the electrodes, the gap is too small and needs to be widened.
If the tool fits closely to the specified measurements, the spark plug is ready to be installed.
Adjusting the electrode gap
Hold the spark plug with the electrode facing down.
To narrow the electrode gap, gently bend the bottom electrode towards the other one.
To widen the electrode gap, gently bend it outwards.
- Never bend too much. Always use very light pressure, as spark plugs are delicate and can break easily, causing misfires.
- If you are struggling to adjust the gap with the tool, try pressing the electrode gently against a flat surface like a table.
After adjusting the electrode gap, make sure to re-measure it so that it is correct for your specific product.
Correct electrode gap for my Husqvarna product
Depending on the product in question, the electrode gap can vary.
Always check your product’s operator’s manual for the correct electrode gap.
