battery voltage ranges

rasbury

I posted this under electrical but did not get any response so thought I'd throw it to the big boat guys....never had such a battery issue....did a run this weekend, a 100 gallon run! Can't do that to often! Anyway, here is the story......put the boat in for the first day run. I always use batter #1 to start but keep in mind this is maybe 6th time boat is in the water. Anyway, kind of a limp start but it started and ran fine.  Got about a quarter of the way and around a no wake put it in idle to wait for others and it died....nothing when I turned the key so I switched to battery number 2 and started just fine. Somewhere along the line when we stopped for lunch I checked my connections for new batteries just installed.....on battery number 2 the neg. was loose and on battery number one, one of the "other" wires (has the main wire on the big lug and a smaller wire on a smaller post) was loose. That was a shock...I tightened them back up. I think I then started on battery one again and went on....started the next day on battery one, stopped once on the trip and started on battery one. At the ramp, I needed to restart to get it on the trailer better and battery one was dead, started on battery two. I was going to pull the battery but wanted to check the charging and it started fine....checked the charging voltage and battery one was 13.8 and battery two was 14. something like .1 or .2.....what the heck am I dealing with? I sure ran it long enough to charge from the loose connections and we did not run anything once we got to the dock or the trip home except the radio for a bit......ideas??

rinker270nb

I had the same problem last year.  I replaced the batteries as they didn't have a good load, and then my new batteries were getting tired.  I think the problem is in the alternator.  I put my boat ('99 270) in tomorrow and will put a meter on everything and then see how the alt reacts.  

My thought is that the alt is bad and wearing down the batteries to the point that they don't have a load, as they get charged they can't give the power needed.  If it's not the alt, I am back at square 1.  Good luck and I will post my results.

Black_Diamond

If it is the alt, make sure you get a marine one to replace it.

rasbury

I am reading in the forums searching battery switches, extended periords of idle is an issue because it's not charging and was in extended idle zones....will read more but here is a weird thing....the issue appeared to be battery one per above and I wanted to make sure which battery number one..the wires looked to match up but can't see up to the switch so I pulled the wire and turned the ignition and it was hot...so I put that battery wire on and pulled the other leaving the switch on one...and the ignition was still hot.....does the system find a battery either way the switch is turned? My switch has 1 or 2 or both and I sure found that odd...I am testing both batteries but the switch sure puzzled me!