Dual battery question with no engine

[demundus]

I purchased a boat with no engine (yet). I towed it to my lift and put it up. I'll be doing some little things here and there, but for the most part the boat is solid and doesnt really need too much. There is a switch and it appears there was once a dual battery set up there. This is my first boat of my own, and while i have a lifetime of experience on family boats, ive never had to handle electronics in this respect. I've looked at the wiring diagrams here and they make sense, so ill probably redo all the wiring so i have a piece of mind. But my real question is, how do I handle both batteries with no engine at the moment. I plan on getting a two stroke 200hp merc or something similar, of a 90-96 vintange.

How do I charge my batteries until I get an engine (running auto bilge to keep rain water out)?

When I get an engine, will the engine i said i'm seeking have an alternator to hook the terminals too? Or will I need another piece of hardware?

How do I know which batteries are right for me for now and in the future with the engine?

Do I need an isolator for these two batteries?

relevant Specs:
fishfinder
Radio
regular amount of gauges in the gauge cluster
at some point a 175-225 outboard
20 foot bowrider
dual battery switch already installed with heavy gauge wiring

If theres anything else you can think to add, feel free. Thanks for your answers!

 

[drewpster]

Re: Dual battery question with no engine

How do I charge my batteries until I get an engine (running auto bilge to keep rain water out)?

I would not leave the batteries installed. I would remove them and store the boat with the bow raised and the drian plugs out. Let the rain water drain instead of pumping it out.

When I get an engine, will the engine i said i'm seeking have an alternator to hook the terminals too? Or will I need another piece of hardware?

No The common connection on the battery switch goes to main power on the engine. Usually at the starter.

How do I know which batteries are right for me for now and in the future with the engine?

This depends on the exact engine you end up with. It should have a recommendation from the factory.

Do I need an isolator for these two batteries?

This depends on how you intend to charge them. If you have a 1-2-both type battery switch, the both position can be used to charge them while the engine is running. You have the option of adding an isolator if you would rather both batteries get charged automatically, without having to remember to set the battery switch to "both".

 

[demundus]

Re: Dual battery question with no engine

I guess I had forgotten about elevating the bow. Gotta start thinking of these things again. Thanks for the input!