Outboard not charging battery

Puffer · 07-18-2006, 05:46 PM

I have a 1979 Johnson 115hp outboard engine and I am wondering how to do a check to see if it is charging while running. I have a new battery but I end up having to charge it at home on the trickle charger after using the boat a couple of days in a row.If it is not charging after a check what may be a likley suspect?

Blind Bobber · 07-18-2006, 09:19 PM

Put a D.C. volt meter across the battery and take a reading running and not. Voltage should go up when motor is runing if the unit is charging. What does your manual say the charging rate should be?

BLIND BOBBER

Starfish · 07-18-2006, 09:41 PM

Could be a blown fuse or a burned out diode.

duckboy · 07-23-2006, 04:47 PM

Wouldnt the situation indicate a hosed alternator?

lucky2 · 07-25-2006, 01:58 PM

Probably the diode, or possibly the stator under the flywheel is no good. The stator has 2 different sets of windings, 1 powers the ignition system while the other charges the battery, so your motor will still run without the charging system working.

You can test the voltage with the motor running. It should read around 14 volts. If it stays near 12 volts while running then the charging system isn't working.

troutski · 07-25-2006, 07:13 PM

Some times it is the simple things, check the terminals on the batt..if there is corr. clean and check the cables, sometimes the corr. will even move up the insulation a bit, cut and reconnect - may be even solder the ends to the connectors. Hope this helps.

EULACHON · 07-26-2006, 05:31 PM

Put a volt meter on it should have about 11 volts at idle and 13 or so at speed.

Make sure the depth finder is off when you come in (done that)

If you need a volt meter let me know.

Paul