Testing the coil on a 60-horsepower Johnson outboard's ignition coil is a two-step process. The first part of the test lets you discover whether or not the problem results from a short in the system. The second part of the test tells you whether or not the coil is in good order. If a problem is encountered, a resistance test allows you to determine whether it stems from the coil or from the wiring connected to the coil.
Set the digital multimeter to read AC voltage to 500 volts. Loosen the screws on the five-pin connector between the power pack and the stator -- the ignition charge coil -- beneath the motor's flywheel. Pull the connector from the power pack.
Connect the multimeter's red lead to the power pack terminal with the brown lead from the charge coil. Connect the multimeter's black meter lead to a good engine ground. Crank the engine. Ideally, the multimeter will indicate no voltage.
Move the multimeter's red lead to the terminal with the brown lead with a yellow stripe that comes from the charge coil. Crank the engine. Again, no voltage will be present. If the test for either the brown or brown-and-yellow lead indicates that voltage is present, the charge coil or charge wiring harness has a dead short to ground and needs replacement.
Move the multimeter's red probe to the terminal with the brown-and-yellow lead and the black probe to terminal for the brown lead. Once more, crank the motor and note the charge coil output. A reading of 250 volts or more indicates the charge coil is operating correctly. Reconnect the five-pin connector. If the reading is less than 250 volts, check the wiring and perform the test sequence again. If the voltage remains below 250 volts, move to the next step.
Leave the five-pin connector disconnected. Set the multimeter to the Ohms scale. Move one probe to the brown lead and one to the charge coil and note the resistance. Move the probe from the brown lead to the brown-and-yellow lead and note the resistance. The resistance for both should fall between 750 and 950 ohms. Readings outside that norm indicate a problem with the wiring harness.
Reconnect the wiring and battery cables -- the red cable first -- when you've completed all of the testing or repairs.
- "Evinrude Repair Manual -- 2.5 to 250 HP Models, 2002-2007"; Seloc Marine; 2007
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