1990 Johnson Evinrude "ES" Colt/Junior thru 8 Service Manual, P/N 507870, Page 106Get this manual
ill plugs installed and torqued in the cylinder headIf neces-
I':AAll cranking output tests must be performed with spark
sary to remove the spark plugs, be sure to keep the spark tester away from open spark plug holesThe following series of steps 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
STEPTOTAL OUTPUT TEST
Twist and remove the spark plug leads from both spark L!J plugsf21 2Adjust the gap on the spark tester to V2 in(12 mm)Connect leads to the spark plug leadsSecure tester clip to clean engine groundTo prevent possible arcing of high voltage, route tester leads at least in(51 mm) from any metal surface"'" To avoid possible shock hazard, do not handle ignition coils or spark tester during cranking tests3If equipped, install the emergency ignition cutoff switch clip and lanyardCrank the engineSpark should jump each tester gap alternately If tester shows good output on both cylinders, go to STEPRUNNING OUTPUT TEST If tester shows good output on one cylinder, go to STEPIGNITION PLATE OUTPUT TEST If tester shows no output, go to STEPSTOP CIRCUIT TESTIt is possible for the ignition system to have problem but still produce good outputIf the engine "pops" or "backfires" during starting, the ignition may be out of timeCheck the following: Coil primary wire routing Spark plug lead routing Flywheel condition and location Synchronization and linkage adjustments