How to Gap Your Ignition Coil
Universal · 5 min
The air gap between your ignition coil and the flywheel magnet controls spark strength. Too wide and you get weak or no spark. Here's how to set it right.
What you'll need
- Feeler gauge or business card
- Socket set
- Flathead screwdriver
Steps
Locate the coil
The ignition coil sits just outside the flywheel, usually under the recoil starter or shroud. You'll see two small bolts holding it to the engine block.
Loosen the coil bolts
Back the two bolts off just enough that the coil can slide toward and away from the flywheel, but still holds position.
Rotate the magnet into place
Turn the flywheel by hand until the magnet (the shiny section on its edge) lines up directly under the coil.
Set the gap
Slide a feeler gauge set to 0.010 inch — or a folded business card — between the coil and flywheel. Push the coil against it so it's snug.
Tighten and remove
Hold the coil firmly against the gauge and tighten both bolts. Then rotate the flywheel to pull the gauge free.
Mechanic's tip
A standard business card is almost exactly 0.010" thick — a perfect field tool if you don't have a feeler gauge.