1991 Johnson/Evinrude Models "EI" 40 thru 55 Service Manual, Page 126Get this manual
IGNITION OUTPUT TESTS ill 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
The following series of steps will systematically isolate problem area in the ignition systemTo reduce your trou bleshooting time and to avoid incomplete results, perform these steps in the order written
STEPTOTAL OUTPUT TEST
r:jl 1Twist and remove the spark plug leads from both spark plugsf2l 2Adjust the gap on the spark tester to 1 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 (51mm) from any metal surface17023
"" To avoid possible shock hazard, do not handle ignition coils or spark tester during cranking tests