If you had 13.4 volts on a battery not being actively charged, something doesn't sound right with that battery. A fully charged battery should be around 12.7 volts. But then you did say your battery was dead.
Went to West Marine and Western Auto yesterday. I guess it depends on the individual sales/service person, but the Western Auto staff seem to know far more about boat mechanics. We live in a fishing community so I guess West Marine is for recreational boaters and Western Auto is for working boaters.
Last month West Marine couldn't figure out what size spark plug wrench I needed (18mm). Last night they checked the volts but not the amps on my dead battery and declared it was a connection problem. Sounds like something I would do.
Anyway if you have a 9.9, 4-stroke Mercury you'll need a 12V deep cell with about 465 amps of marine cranking and 350 amps of cold cranking. A starting battery might be better for your electric-start outboard but not for your motor lift. Very important is the group size which tells nothing more than the physical size of your battery. You want to ensure it fits in the tray that Stan installed. Mine was a group 27 (27G).
I basically bought the same battery that Stan gave me. The Western Auto mechanic told me that if it lasted seven years without maintenance then it was the right battery. Like Geoff he said to check the battery acid/distilled water level once a year. He said it was impossible to overcharge the battery with the outboard or solar panels. If you use a charger without an automatic cut-off you could overcharge the battery (boils the acid/water). Charging the battery if needed is a good idea, but you need to check the volts and the amps. My dead battery had 13.4 volts but hardly any amperage.
Gel and AGM batteries cost more and may not last as long. Big advantage is that they're maintenance-free and won't leak. Just ensure your fluid-filled battery covers are on tight for those bury-the-rail heels.
I'd be interested in the same. Original GBI batteries going into their seventh year, and the boat has been out of the water for almost two years.
I'll pull the plastic shrink wrap off next weekend and see if the motor will turn over...
> I have the same setup as you do. My batteries stay charged with the
> solar panels. It's interesting to note that although I stored my boat
> under a roof from April 15 through Dec 1 my batteries were fully
> charged when I got the boat out of storage. Seems the ambient light
> was enough to keep them topped off.
> I do notice that my batteries use a lot of water, perhaps because they
> are constantly being charged by the panels. I was warned by an old
> salt to check the fluid often, and he was right.
> Recently, I purchased a battery meter that simply plugs into the 12V
> outlet over the galley. It monitors the batteries during charging and
> also while they are being used, and seems to work great. I can measure
> voltage drop while using various combinations of equipment (radio, nav
> lights, etc.). I have been very pleased that on bright sunny days I
> can use the VHF radio and my Ipod (for navigation and music) and
> charge an external portable speaker without any battery drain.
> My motor is hard wired to battery 2. When cruising I set my battery
> switch to battery 1 to keep battery 2 fully charged for restarting the
> engine. I haven't, however, done any overnighters so my battery use is
> I still have Stan's original batteries and so I would also be
> interested in what the best replacement batteries are for when mine die.
> Need some battery advice.
> Probably should have replaced my battery long ago. When I need to
> pull-start my outboard in the marina it usually recharges the battery
> enough that I can use the electric start when I'm ready to come in.
> Didn't happen yesterday. By the time I unscrewed everything to get to
> the flywheel I was dangerously close to running into the causeway rip-rap.
> Easy answer would be to replace the battery with the one Stan put in.
> Wasn't sure if there was something better out there now. I've got the
> electric motor winch which I assume uses a ridiculous amount of juice.
> I have one battery hardwired to the motor which is linked to a second
> house battery. Both batteries are linked to two solar panels.
> I've taken zero care of the batteries since I bought the boat seven
> years ago.
> Should I be concerned about the solar panels overcharging the batteries?
> Should I periodically charge the batteries to full capacity?
> Any advice on what battery would be best and what care it needs?
> 1986 Rhodes22 AT EASE
> Kent Island, MD