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mbeach
10-11-2006, 11:56 PM
i usually disconnect my ground battery lead when i will not be using boat for 3 weeks or more. today when reconnecting my battery, i did not notice that the purr of the fuel pump when the system was energized. fortunately, i was in the garage and not on the ramp. anyway, i had 2 dry cells in a 2003 battery. topped off with water and charged for an hour to see if hopefully this was the problem rather than the evil electrical daemon. reconnected and the depth gauge flickered but dash would not light. took to sears and had them test finding a doa battery. new one fixed problem. moral of story is that the maintenance free battery is a mystical marketing tool that stung me. not allowing the 2 cells to dry out would have prevented battery failure. i will check and top off at least twice a year henceforth. boaters beware; you have been warned.

Archimedes
10-12-2006, 12:36 AM
Call me stupid, but I thought any battery that allowed you to open it and add water was not a 'maintenance free battery.' I thought a maintenance free battery was a closed cell battery.

Mi.mc
10-12-2006, 12:38 AM
o.k. you're stupid. just kidding i thought that too

JimN
10-12-2006, 01:19 AM
"The large print giveth and the small print taketh away".

bigmac
10-12-2006, 04:46 AM
If you had two dry cells on a maintenance-free battery, I'd have to opine that it was either very old, severely overcharged, or defective from the mfgr. Usually, a maintenance-free battery can't be opened. Are sure it wasn't a low-maintenance battery instead? Low-maintenance batteries have thicker plates and more calcium than a regular battery, but less than a maintenance-free. LM's do gas more than MF's, especially in hot weather. You can open a LM battery to add distilled water.

Far better to leave the battery on a maintainer/float charger while the boat's not being used rather than disconnecting anything IMHO - sulfation of the plates starts happening at about 12.4 volts. Mount one of those $30 Schumacher charger-maintainers on it permanently - then all you have to do is plug the boat in. That would take less time than disconnecting the negative terminal and would be far better for your battery.

http://us.st11.yimg.com/us.st.yimg.com/I/yhst-85105415359236_1917_1398944

edwinfuqua
10-12-2006, 05:22 AM
i usually disconnect my ground battery lead when i will not be using boat for 3 weeks or more. today when reconnecting my battery, i did not notice that the purr of the fuel pump when the system was energized. fortunately, i was in the garage and not on the ramp. anyway, i had 2 dry cells in a 2003 battery. topped off with water and charged for an hour to see if hopefully this was the problem rather than the evil electrical daemon. reconnected and the depth gauge flickered but dash would not light. took to sears and had them test finding a doa battery. new one fixed problem. moral of story is that the maintenance free battery is a mystical marketing tool that stung me. not allowing the 2 cells to dry out would have prevented battery failure. i will check and top off at least twice a year henceforth. boaters beware; you have been warned.

I have bought maintenance free batteries that had no acid in them when they were purchased. They have a longer shelf life that way. When I brought it home I filled it and snapped the covers on. Now I'm not saying you could not get in it if necessary but it was not intended to be opened after servicing. You can only find stuff like that at a battery wholesaler.

I'm using the SIX PACK type batteries now. They are shock resistant and have been giving good service. They are maintenance free. There are two manufactorers that make them, one is RED and the OTHER Black. Optima is one of them.

I like the battery tender, but be carefull read the instructions carefully on the unit you buy. Some types actually charge your battery to about 80% then put a small load on the battery untill it gets to about 12.5 VDC then it starts charging again. 80% charge is perfect for long storage. Some of the so called maintenance chargers tell you not to leave the charger on for extended periods. Now for a 6 or 700 AMP battery and the max charge is 1 AMP at 13.8 VDC (unlike the big chargers that deliver 15+VDC) you can leave them on there for a few days. But there is one that you can just leave it on year round. That may be the one bigmac is talking about.

Edwin

bigmac
10-12-2006, 09:23 AM
I have bought maintenance free batteries that had no acid in them when they were purchased. They have a longer shelf life that way. When I brought it home I filled it and snapped the covers on. Now I'm not saying you could not get in it if necessary but it was not intended to be opened after servicing. You can only find stuff like that at a battery wholesaler.

I'm using the SIX PACK type batteries now. They are shock resistant and have been giving good service. They are maintenance free. There are two manufactorers that make them, one is RED and the OTHER Black. Optima is one of them.

I like the battery tender, but be carefull read the instructions carefully on the unit you buy. Some types actually charge your battery to about 80% then put a small load on the battery untill it gets to about 12.5 VDC then it starts charging again. 80% charge is perfect for long storage. Some of the so called maintenance chargers tell you not to leave the charger on for extended periods. Now for a 6 or 700 AMP battery and the max charge is 1 AMP at 13.8 VDC (unlike the big chargers that deliver 15+VDC) you can leave them on there for a few days. But there is one that you can just leave it on year round. That may be the one bigmac is talking about.

Edwin

Certainly one should read investigate such a product carefully, but AFAIK, all of the float chargers on the market are suitable for extended periods of charging with zero damage potential to a battery. Most of these are labeled "maintainers", or "charger-maintainers", and will usually detail a "float charge" capability. The ones that come to mind other than the Schumacher are Battery Tender, Battery Tender Plus, and Optimate. Some of these devices (Optimate) even detail the capability of reversing sulfation that's already taken place on a given battery. All of them state that they're suitable for long-term connection to a battery.

The Schumacher maintainer I show above is one that I've had hooked up continuously for close to 10 years to the same lawn tractor battery - the one that I use to power my 12 volt portable fuel tank. I have 7 of those things. Likewise, for many years, my motorcycles and boats are all hooked to one of these things all winter and snowmobiles in the summer.

edwin
10-12-2006, 09:59 AM
*Hijaack - on* - good to see there's another edwin in the house!

TMCNo1
10-12-2006, 06:02 PM
Certainly one should read investigate such a product carefully, but AFAIK, all of the float chargers on the market are suitable for extended periods of charging with zero damage potential to a battery. Most of these are labeled "maintainers", or "charger-maintainers", and will usually detail a "float charge" capability. The ones that come to mind other than the Schumacher are Battery Tender, Battery Tender Plus, and Optimate. Some of these devices (Optimate) even detail the capability of reversing sulfation that's already taken place on a given battery. All of them state that they're suitable for long-term connection to a battery.

The Schumacher maintainer I show above is one that I've had hooked up continuously for close to 10 years to the same lawn tractor battery - the one that I use to power my 12 volt portable fuel tank. I have 7 of those things. Likewise, for many years, my motorcycles and boats are all hooked to one of these things all winter and snowmobiles in the summer.

I have the Battery Tender Plus and have used it over the winter months on my 1998 John Deere LT155 mower with the original 1998 JD battery since new, it's still in the mower and cranked up today in about 2 seconds. I still can't believe it's 8 years old and holding it's own.