2003 Johnson ST 6/8 HP 4 Stroke Outboards Service Manual, PN 5005471, Page 73Get this manual
IGNITION SYSTEM TESTS
SYSTEM TESTS
The following series of tests will systematically isolate problem area in the ignition systemTo reduce your troubleshooting time and to avoid incomplete results, perform these steps in the order written
To prevent possible arcing of high voltage, route tester leads at least in(51 mm) from any metal surfaceInstall the emergency stop switch clip and lanyard assemblyCrank the engineSpark should jump each tester gap simultaneously If tester shows good output on both cylinders (8 HP), go to Running Output Test If tester shows good output on one cylinder (8 HP), go to Ignition Coil Tests If tester shows no output, go to Stop Circuit Test
IMPORTANT: All cranking output tests must be performed with spark plugs installed and torqued in the cylinder headIf necessary to remove the spark plugs, be sure to keep the spark tester away from open spark plug holes
Total Output Test
Running Output Test
CAUTION