Outboard Recharge of Battery

[Randy Kolb]

I have a Honda 9.9 horse 4 stroke that can charge a battery. I'n need to purchase a plug and make up the cable. My question is for the limited time I run the motor (maybe 30 minutes each time out 3-4 times a week) will I get a benefit from this? Is that enough time to do any real charging? Thanks

 

[Charlie on]

Same question?

I have a 9.9 Merc with electric start & charging. Towards the end of last season, the electric start stopped working. I believe, but don't know, that the voltage in the battery dropped low enough that it won't turn the starter (it starts right away with the pull rope) I checked the battery when I took it home at about 11.3 volts. fully charged it went to 12.5. My question is, is that enough of a drop so the electric start won't work, and why doesn't the battery charge fully when the moter is running?Any answers will help.thanks

 

[Gary]

Battery Charging

First it depends on how many amps your charging system puts out how much good it will do. The other thing is how much power you use on your boat every time you use it. If you only use your VHF radio & a depth sounder, 30 Min. to an hour of charging from your outboard each trip will help a lot. If you use more power acc. & run your outboard less it won't be enough, but the way I look at it every little bit helps.

 

[Aldo]

Charlie: Battery Voltages are:

Charlie: A 12 volt battery will measure: Full = 12.7 volts, 3/4 = 12.45, 1/2 = 12.2, and 1/4 = 11.95, and Empty =11.7 volts. (These values are, of course, after the battery has had a chance to cool down after charging has been completed). For long life, you shouldn't let it go below half. If your's was at 11.3, it's probably dead, and that is why you can't fully charge it with your generator from your motor, and probaby why it won't start your motor. There is plenty to read about battery charging and there are video tapes on the subject too. This is important even on bigger boats. We use a solar panel to charge our battery, and that's nice because the battery is always fully charged when we get to our boat. My battery's is getting old now, and I will also probably have to replace it this summer. We use a size 27 battery which is bigger and has more capacity. Aldo

 

[LaDonna Bubak - CatalinaOwners.com]

Charlie, time for new batteries

Definitely sounds like yours is dead. You might want to check out Nigel Calder's book on Boat Electrical Systems (name?) - it'll help teach you how to maintain your battery/ies properly to eek out the most juice.Randy, I agree with Gary that every little bit helps. If your use is low, the little bit the engine charges will keep it topped off without burning it up.LaDonna