24V Trolling motor Charging Problem on 89 Astro

[robinr011]

Hello,
Hope some one can help with a problem I now have. My 24v Mercury trolling motor uses a high current three prong plug that plugs into the deck control panel and is controlled by a three way switch. The switch is labelled "Run / Off / Charge. My problem, in the past I would use a modified portable battery, (replaced the alligator clamps with a high current 3 prong plug and would just plug it into the trolling motor receptacle and flip the control switch to charge and away we would go. Last summer the portable died and I bought a new replacement, wired it the same way, plugged it in, and nothing. Charger acts like dose not even see the batteries.... Any thoughts

[Jonestrollingmotor]

I would make sure I wired the plug correctly first. The charge/run switch you're talking about changes from series to parallel for the two batteries. Also, those switches have been known to go bad. You should take the panel off and make sure the switch hasn't burned.
John

[billnorman1]

BTW if the batteries are dead it might not "see" them,

[robinr011]

Thanks guys... I also noticed that this charger was only 12V, if the batteries are in series I would need a 24V....Correct?

[Lou r Pitcher]

no, connect 12v charger across only one battery at a time .

[billnorman1]

Thanks guys... I also noticed that this charger was only 12V, if the batteries are in series I would need a 24V....Correct?

OOPS. A new can of worms. Was the old charger 24 volts?

[robinr011]

hummm, not sure.. It was old and I would have to think it was only 12V. John made an interesting comment.. When you plug the charger into the trolling motor receptacle and flip the switch to charge does that change the circuit to parallel instead of series? If that is the case the 12V charger should work, (if wired correctly).

Robinr01