I have a 1984 70hp Johnson. The charging voltage goes to 15 volts or higher at wot. It only has a 6 amp charging system but at high speed I have to turn on accessories to keep the voltage down. This motor uses a rectifier with no voltage control so I retrofitted a rectifier off of a John Deere that also regulates voltage by dumping current to ground when the voltage gets to 14 volts. The charging system works great this way but when it starts to dump current, the tachometer goes crazy. When I hook up the oem rectifier the tach works. Is there another rectifier I can use that will control the voltage without affecting the tach? I see that Mercury uses a 2 wire rectifier that has a separate tach terminal. Thanks, Keith
