Maintaining starter batteries

[RL]

I have 4 Interstate 12 volt "31-MHD" starter batteries. I'm preparing to store the coach for 8 months. Any suggestions as to what I should buy? They have an estimated rating of 115 amp/hours if that's the correct term, so they are big strong batteries. Being in sunny, praying for rain California I would be interested in information about solar maintainers if anyone has been successful in using that. Thanks.

Bob

[expressbus]

Bob,

Don't know about solar panels. I do know that for almost seven years I have been using a Guest charging unit mounted on the back wall of the engine bay to keep my chassis batteries up. It has a high charge/middle charge/float charge rate. I liked it so much that I installed a second one to keep the house batteries charged up too. All you need is a 30 amp duplex outlet, an extension cord, and a plug wired onto the charging unit.

I don't recall the specific model numbers but expect to go to the bus garage tomorrow and will endeavor to get that info plus some pictures.

Will
steelrails@nc.rr.com

[luvrbus]

Use a single wire with leads and clamps for each battery post both + and - hook the charger to both ends of the leads + and - all 3 batteries will receive the same amount of charge it's been done like for years you can make a lead  or pay 100 bucks+ for a lead, just size the wire for no voltage drop at the end of the last battery, solar chargers are not that well regulated I would pass on it myself  

good luck

[Oonrahnjay]

...  solar chargers are not that well regulated I would pass on it myself  
good luck

    Yeah, very important point.  If you're going to leave the bus (or batteries, if out of the bus) untouched for 8 months, you're going to want to have a *very* precise charging system.  I trust a good quality 'float charger' but, even in the winter, I like to check to see that everything is OK every 2-3 weeks.

[Oregonconversion]

I found a 24V electric moped charger on ebay for $5. I hook it up to turn on 10 min a day. I think these batteries are almost 7 years old, but I have had this system in use for close to 5 years now.

If I were to do it again I would buy a battery tender just to be sure. As for solar panels I would go with the mono-crystalline solar cells. They last a lot longer and are supposed to be more efficient too I think.

I have one of these for a 12V charging system and it works great so far. I have only had it for a couple months though.

http://www.amazon.com/gp/product/B004FOEUI0/ref=oh_details_o00_s00_i00?ie=UTF8&psc=1

2 of these in parallel would do the trick but you would need a 24V controller to stop the charge when the batteries are full.

[lvmci]

Hi All, I bought 2 battery maintianers at harbor frieght, wired individually to each group 31 starter battery, stuck a 4 plex flat trailer connector thru the wall into the bay, wired an opposite trailer flat connector to the two positive/negative wires of each charger, mounted them next to the on/off starter knife switch, ran an extension cord from the bay 110 ac plug, when I throw the starter batteries to off I plug in the maintainers, when plugged into a post, unplugged when running the bus, they have indicator lights on them when fully charged, that I see when throwing the knife switch and pullimg the trailer plug, lvmci...

[TomC]

For business reasons, I have my truck in a storage yard. I have a solar battery maintainer that is about 18" square. I have it hooked up to the 4-31 batteries and so far have not had any problems starting the truck-even after sitting for several weeks. Got it at Camping World. Good Luck, TomC

[gumpy]

If it's only for 8 months, I would simply make sure they are charged, unhook the negative cable, and walk away.

[gus]

Do not use a cheap float charger for that long time, it will dry the cells.

Use some kind of smart charger - I use both Battery Minder and Battery Tender which are the same as far as I can tell after many years use.

I prefer the Battery Minder only because if plugs in directly and eliminates one cord to get tangled, they cost about the same.

[jjrbus]

If it's only for 8 months, I would simply make sure they are charged, unhook the negative cable, and walk away.

I'll second Gumpy, here.  Keep it simple.  JIm