set-up for 2 batteries on an I/O?

[fishnbuddy]

The starboard battery is wired to altenater...charges fine. The port battery is not wire to the eng and has to be externally charged after every trip.

Here is the question...Can I wire the port battery into the alternater also. Its more practical to have it charging while running the eng, than go through the hastle of charging it after every trip! Will it affect starting the I/O or affect the altenater? I know ideally I would want the 2 batt selector switch and I will eventually change it to that. But for now...can I do this with out damaging any thing?

Thanks for any 2cents you throw in!!
...fishnbuddy

[stix]

Get a battery combiner or battery isolator. Basically it will charge your starboard battery first, once fully charged it will set the alternator to charge your port battery. That way your alternator takes care of both batteries. You will still need something to maintain or recharge your batteries when you store it though....either shore power or Solar charge panel.