will my 16 amp alternator charge my 3 batteries?

[tigertank]

Hello, i have a Lund 1775 tiller with a 75 horse honda outboard. I have 2 trolling motor batteries in parallel, the starting motor has a battery on it's own. I hooked up a minn kota 20 amp 2 bank charger. I just found out that we may not have power to run a cord where i'll be fishing for the week and don't want to try a generator since burning up a charger once before. What I did is run another 6 gauge positive from the big motor battery pos-pos & neg -neg to the trolling batteries. Will the 16 amp alternator on the honda charge the 3 batteries safely without alternator damage? Thank you for any replys, Al.

 

[MH Hawker]

Re: will my 16 amp alternator charge my 3 batteries?

it should but it will need to be ran at WOT for several hours

 

[glenn property of pam]

Re: will my 16 amp alternator charge my 3 batteries?

now you have linked the trolling batteries to the motor battery when you troll you will be pulling power from all 3 which is not a good idea. the 16amps is 16amps at high motor rpm in perfect conditions per hour so if your trolling motor uses say 55 amps per hour then you would have to run at full power for about 4 hours to refill the batteries which is proberly unfeasable. it will not damadge the alternator.

you could install a automatic transfer relay that will send power to the trolling batteries when the motor battery is full which would solve the risk of ending up with 3 flat batteries but with 16amps available a onshore charge would realy be the best option.

 

[tigertank]

Re: will my 16 amp alternator charge my 3 batteries?

thank you for the replys, i will undo the starting battery when just casting the shores and such so not to run it down. I fully understand that they won't charge, but hope to get the week out of them being charged from the motor so i don't have to yank them out of the boat. Maybe looking next year into a minn kota onboard dc alternator, may help the issue. The big motor has a trolling plate when i use the downriggers, so that will charge then. Had a bad time few years back when a generator charging 3 boats fried 2 onboard chargers on us.

 

[Silvertip]

Re: will my 16 amp alternator charge my 3 batteries?

I think you missed the scope of this issue. The trolling batteries will be losing ground at a rate 3 times faster than the engine can charge them and that's with the engine running wide open -- constantly. For every hour you run the troller you need to run the engine wide open for three hours just to replace that current. Of course that all depends on how fast you are tolling and for how long. Alternator output at trolling speeds with the big engine will be of no value whatsoever.

 

[tigertank]

Re: will my 16 amp alternator charge my 3 batteries?

I get you Silvertip, i will have the main engine battery not hooked in the parallel series when i get to where i will be shore casting so not to run that particuliar battery down. I just want it to get me through the week then will get a much more efficient and proper way to do this next season. Thank you and I appreciate all the replies. I wish i could figure out how to get my post replies sent to my email or notifications, geez.

 

[glenn property of pam]

Re: will my 16 amp alternator charge my 3 batteries?

years ago we use to have a old pick up that we would put the battery in the back off and charge up while we ran into town etc (uk has a diffrent tow plug that can supply power on one pin not sure if u.s is the same way) the truck had a 60+ alternator so that may be a option if you can not get shore power.

 

[Silvertip]

Re: will my 16 amp alternator charge my 3 batteries?

There are lots of inverter generators available today that would eliminate that issue (if the charger was the issue to begin with). Those generators, as do most non-inverter types, have a direct 12 volt charging outlet on them that provides 8 amps of charging current.

 

[babbot]

Re: will my 16 amp alternator charge my 3 batteries?

The larger trailer plugs here have the power feed as well. That is s good idea since a newer truck will have quite a large charger. Not sure if you get all the current through the trailer plug though. Trucks with plow packages have huge alternators. i think mine has a 220 amp(course this not at idle)
As soon as you hook up your spent trolling motor batteries to your starter battery they will start drawing power from the starter battery since it is probably fully charged. You need somthing in the middle to stop the draw. The "weaker" batteries will try to pull power from the stronger batteries. Thats why they tell you to always replace batteries in pairs and of the same size/type.

Also, go to your settings in iBoats. There is some setting to default the notifications when you reply.

 

[tigertank]

Re: will my 16 amp alternator charge my 3 batteries?

thank you