1996 Johnson/Evinrude Outboards 8 thru 15 Four-Stroke Service Manual, Page 106Get this manual
Output TestsModels
All cranking output tests must be performed with spark plugs installed and torqued in the cylinder headIf to remove the spark plugs, be sure to keep the spark tester away from open spark plug holes
STEPTOTAL OUTPUT TEST
To avoid electrical shock, do not handle ignition coil or spark tester during cranking tests1Twist and remove all spark plug leads2Adjust the gap on the spark tester to 38 in(9 mm)Connect tester leads to the spark plug leadsSecure tester clip to clean engine ground