1991 Johnson/Evinrude EI 60 thru 70 outboards Service Manual, Page 126Get this manual
IGNITION OUTPUT TESTS
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 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
IT] 1Twist and remove the spark plug leads from all spark plugsf21 2Adjust the gap on the spark tester to 12 in(12 mm)Connect tester 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