1989 70 hp johnson--battery charging system

[hntndude]

just started over charging.as rpm increases,so does the voltage.too high-up to 16 volts.checked all connections,changed battery,checked output

at gauge & battery---same. switched rectifier with one from another motor. nothing changes

 

[Will Bark]

On other threads in the forums you will see those that say an unregulated system that is normal and you can hook up a radio or gps or something else to the battery to drain off some of the voltage. My 15 Rude does this all the time and so far nothing bad has happened over the20 years its done it.

 

[fmarando]

My 1985 Johnson 70 does it too. My batteries typically last 6-7 years so I don't think it's a problem.

 

[Boobie]

Just remember to use a battery you can check the water level in.

 

[joereeves]

As above.... That engine does not incorporate a voltage regulator, just a rectifier that converts AC voltage to DC voltage to directly charge the battery. It's a setup that has been used for years and does not cause any damage. A 12v charging system but of very low amperage.

 

[papyson]

did you just put a new battery on it?did you put a sealed no maintenance one?....these rectifier only charging systems were designed before todays batteries...16volts will probably last forever but if it goes much higher you will probably lose a rectifier sooner or later...using a battery that you add water to is the proper way to go...watch your tach....it will start getting erratic sometimes before the rectifier is completely gone..