115 johnson charging question

[kenny]

Have a 1990 115 johnson that volt meter stays exactly at 12 volts. My old 90hp would show 13-15 volts as it ran. In the repair manual I see this 115 has a regulated charging system where the old 90 was unregulated. How can I be sure its charging? I always throw the charger on for a few hrs before I take the boat out so its hard to tell. Any quick way to test the charging system? Thanks.

[joereeves]

"Kenny..... You asked, and stated: ". How can I be sure its charging? I always throw the charger on for a few hrs before I take the boat out so its hard to tell."

You should have a tachometer on your boat. If you do not, I suggest that you get one. Besides having it show you an accurate accounting of your engines performance, it also shows that the charging system is operational.

The tachometer operates off of the charging system pulses. If the tachometer is working, the charging system is okay.

Throwing a charge into the battery before you take the boat out is fine, however... if you should ever accidently hook those charging cables up backwards and turn the charger on, you will damage the rectifier portion of the charging system which is a rather expensive item.

Joe[img][/img]"