Help Rewiring

I've torn apart my boat for refinishing the interior. Its an old slickcraft and there have been a multitude of things wired, removed, wires patched into, blah, blah. I've taken out all the wiring that isn't related to the original mercruiser 165. I'm starting anew with all the other wiring using red and black (there were some interesting color combos removed) and I need advice on what to hook up to each battery. I'm adding a Yamaha T-8 kicker. I have a dual purpose starting battery and a deep cycle battery. The Dual will be for starting the big engine. I will wire the Yamaha to the deep cycle. There is no selector switch on the boat. I'm not sure that the alternator charges both batteries either. I'll have to take some pics of the wiring configuration back there. I use this boat primarily for trolling for salmon on the great lakes. The big motor won't run much. I'm concerned about keeping my electronics running over the course of a 6-8 hour fishing day. A list of what i need to power:

Running lights, on board lighting at night.
Fish Finder
GPS Plotter
Marine Radio
Moor Subtroll
Bilge Pump
Controllking (rheostat speed controller for Yamaha)
Downriggers

Thinking about installing an on-board charger

Please help me get this right

Re: Help Rewiring

look at the top of this forum. there are 2 sticks that cover wiring. if you don't find your answer, then ask specific question.

Re: Help Rewiring

tashasdaddy said:

look at the top of this forum. there are 2 sticks that cover wiring. if you don't find your answer, then ask specific question.

Click to expand...

Thanks! I have been reading extensively, including those sticky's. It's just all a bit overwhelming for me. I'm not that smart. I'm confused about where to draw the line, i guess, with what i need.

The yamaha has a 12 amp alternator, i believe. So, at half throttle, that's 6 amp output, correct? I don't know if that's enough output to maintain charge with the list I have above (assuming full charge and healthy battery to start).

If the yamaha has an alternator and the alternator from the inline 6 is charging just the starting battery, should i put in an isolator and feed it to the house battery as well?

The list of options is endless. I guess I'm looking for direction on what will do the job for me without breaking the bank.

Re: Help Rewiring

I would keep the inline motor and battery by themselves, especially if you don't run it much. If you like, you can tie it into the deep cycle battery bank with either an isolator or battery switch, depending on whether you prefer automatic or manual. But the fact that it doesn't run much tells me that you will get little out of it. One cool thing about a manual combiner switch is that you could draw on the trolling bank to help start the big motor if its battery was dead.

As for making 6 amps from the Yamaha at half throttle... Maybe. Yamaha should have an alternator output curve available (Tohatsu/Nissan does) to show the output at various RPMs. I doubt that the 6 amps (if available) would be adequate to make up for any significant amount of electric trolling motor use, but for lights and accessories, etc., it should work fine.

Re: Help Rewiring

thanks pvanv. no trolling motor, just lights and accessories. lights are not on much when fishing. Jumper cables and no switch would be just fine in case of emergency big battery failure, no??

Re: Help Rewiring

Yes, I suppose that to go "on the cheap", jumper cables would be OK. The big question remains whether your OB alternator will produce enough output for the House bank. Assuming the relative light loads you are describing, there's a good possibility it will work just fine.