The coil on a Poulan chainsaw sits inside the ignition module. These two parts are connected, so you must replace them together. The coil and the ignition module are responsible for developing, holding and discharging the high voltage spark needed for combustion. If these parts aren't working correctly, you won't be able to get the engine to fire properly and may experience hard starts and erratic performance. Due to the high voltage contained in the coil, you must take all safety precautions, as electrocution may occur.
Lift up the rubber boot, which is attached to the spark plug. Unscrew the plug with the socket wrench and 3/8-inch socket. Remove the plug from the cylinder. Unscrew the four bolts holding the fan cover in place over the starter unit. Lift the cover up, then pull it down to free it from the engine.
Disconnect the short circuit wire from the tag on the side of the ignition module. Place the flat end of the screwdriver underneath the tag and push the wire up. Undo the two retaining bolts holding the module in place on the crankcase. Lift the ignition module away.
Unscrew the ignition lead wire, the thicker wire, which runs from the module to the plug, counterclockwise while wearing leather gloves. Don't pull the ignition lead wire from the retaining clips if you are only replacing the coil and ignition module.
Push the short circuit wire into the tag on the side of the new ignition module, making sure it's secured into the retainer. Place the ignition module into the crankcase. Push the ground wire into place under the lower retaining screw. Thread the lower mounting screw in halfway. Thread the upper mounting screw and tighten about halfway. Tighten the ignition lead wire clockwise against the new module.
Rotate the flywheel by hand until the magnets on the flywheel line up with the arms on the ignition module. Press the setting gauge into the space between the arms and the magnets. Press the ignition module against the gauge while tightening down the retaining screws the rest of the way.
Lift away the setting gauge and insert the feeler gauge in its place. Make sure the air gap is set to .025 to .03mm. Refit the fan cover and tighten down all four retaining screws.