1976 Evinrude 40HP outboards Service Manual, Page 37Get this manual
bPower testIf the ignition coil is good, the tester's meter will fall within the good area, with the primary circuit adjusted as specifiedConnect the test leads from the ignition tester to the coilConnect the red lead of the tester to the blue lead of the ignition coil and the tester's black lead to the coils black ground leadConnect the high tension lead of the tester to the high tension (secondary) of the ignition coilWith the tester set to coil index (or operating amperageMerc-O-Tronic with model 55-980 CDA Adapter) adjusted as specified, note meter readingSee Figure 4-23A low reading on the tester indicates weak coil which must be replacedA dead coil will show no reading ,1-;; E