1985 OMC 65, 100 and 155 HP Models Commercial Service Manual, PN 507450-D, Page 181Get this manual
3Reverse the ohmmeter leads and note readingAn infinite (very high) reading in both directions indicates the diode is open low ohms reading in both directions indicates shorted diodeA normal diode will read resistance in one direction and infinite reading in the other direction4(f diode is defective, replace power pack 97
Charge Coil Tests 1Separate two-wire connector between charge coils and power packPlug both ends into adapterSet meter switches to negative (-) and 500 scalesAll adapter switches "On 2Place red meter lead in pinhole "A" and black meter lead in pinhole "8 Start engineIf meter reads 250 volts or higher charge coil is OK 3No or low meter indication in above stepturn" A" and "8" switches to "Off" and crank engine Meter should indicate 160 volts or higherCharge coil OK4Charge coil short testAll adapter switches "Off," place meter black lead to engine timer base assembly Place red meter lead alternately into pinhole "A" and "8 Crank engine, meter should not indicate, any indication on meter other than zero, charge coil shortedRepair or replace