1973 Chrysler 707HE 70HP

[JHurwitz19]

Hello all, I am new to this and just finished restoring the outer shell of a 1962 Lonestar Biscayne Biat. I have moved onto the electrical wiring and motor now. I replaced all of the original wiring one by one, however as I’m a newbie to the marine engines, will a motor that old have charging capabilities of the cranking battery? Should I run a separate power source to utilize for accessories such as a horn, LED running lights, gps/fish finder combo? Any help or advice will be greatly appreciated.

 

[Tassie 1]

Of all the bits and pieces you've mentioned the only thing that will be on a lot will be the fishfinder/ chartplotter,
you don't use a horn much at all,

Nav lights when it's poor light or dusk,

l wouldn't consider going out late at night or all night with a 47 yr old Chrysler, specially if in coastal waters,

And l've had 10 or so Chrysler motors, including two 70's

A second battery is always a good thing to have regardless.

 

[JHurwitz19]

Thank you Tassie, I will look into obtaining a second battery for the accessories. Then I can use the other one strictly for cranking the motor. Thank you for your input. How long will a battery typically last on a full charge while running a fish finder/chart plotter?

 

[Tassie 1]

In the real world l really cannot say how long a fishfinder/chartplotter will last on a single fully charged battery,
There are so many models with many different options

it's a bit of a piece of string question

keeping in mind that most modern electronics will turn off automatically when voltage drops below a certain point,

 

[jerryjerry05]

If properly wired? your motor should charge the battery.
New hot battery should last a long time.
Myself I never killed one even fishing all day.
A second one hooked up correctly is a good idea.

 

[JHurwitz19]

I wired a second battery and tested the outgoing amps to discover that the motor does in fact charge the battery. Thank you guys for your help!

 

[jerryjerry05]

Don't use a deep cycle as a starting battery.
The charging system on most outboards isn't designed to charge them.
It can damage the system.

 

[JHurwitz19]

I have a cranking battery in there as my starting battery, then I installed a battery selector switch and the deep cycle battery. The deep cycle battery handles the lights, electronics, etc. Thanks again!