Got in a hurry a couple of weeks ago and left battery switch on and now both batteries dead.

Can I charge both simultaneously by hooking charger to one and putting switch to "all" or should I charge each separately?

15 mile trip to boat so I would prefer to make one trip BUT we have not been out in 3 weeks and have a babysitter lined up for Sunday and mommy and daddy desparately need some quiet time (girls are 3 and 6) and if it means making 2 trips to be sure both charge completely, I'll do it. (heck, I'll buy 2 replacement batteries if it means a trouble-free Sunday cruise)

If the batteries are the same age and both are down the same amount it should work. The problem you run into is when one is down more than the other. It will continue to pull power from the charger and overcook the better battery. Eventually this kills both from overcharge. But if you are just doing a short recharge you should be fine. Formula normally wires their boats with a 2 leg charger so each battery gets the proper charge, but I'm guessing you are using a standard off the boat charger.

Thanks for the advice. I decided to just pack a beer cooler and drive down this afternoon and charge the batteries individually. Used my handy dandy die hard commercial grade charger and hit each battery with a 50 amp charge to see if they would take the juice. After 20 minutes per battery, each was decently charged (enough to crank an engine) so I left the boat with a 140 minute 15 amp charge one one battery. Sunday I'll swap and charge the other while we clean the boat then, once cranked, run the boat on the 2nd battery for a while.

Once again, thanks for the suggestion!

Steve,if those batteries are the originals from when we sold the boat new,you might want to consider 2 new ones at some point,as they may be near the end of their life. Don't remember if we ever replaced them when you bought it.Tough getting old,can't remember much. Robert