Winter Battery Maintenance Suggestion

[Stale Trooper]

I read somewhere about a gentleman who had a diesel pickup that was in long term storage during the winter months. He wanted to keep the vehicle, which was located in a northern state, in a serviceable condition to the point that he could reliably go to the vehicle, and be able to start it whenever he needed to use it.

He talked about the fact that he already had a block heater, and it was kept plugged in all winter long. His concern was having enough power in the batteries, to be able to start the truck when it became necessary, without bringing jumper cables when he wanted to use the truck.

This got me to thinking, and having two 2nd Generation Dodge Ram Diesel pickups that were somewhat in the same situation, (parked for long terms during the ‘off’ season). So, I developed a means of not only heating the engine, but also safely keeping the batteries fully charged, while utilizing a single extension cord.

NOTE: Usual disclaimer applies; I am not responsible for any loss, injury, damage to persons or property if you follow these instructions. I provide these instructions with the assumption that the reader is at least knowledgeable enough to know his/her limitations. If you are unclear, or unsure, of how to accomplish this project, take your vehicle, and these instructions to a reputable mechanic, and pay him or her to complete the project for you.

The plug in: I bought a 3 way plug in with a short (24”) #12 extension cord from Harbor Freight (http://www.harborfreight.com/3-way-g...ord-61998.html $4.99). This item has sliding covers to protect the receptacle contacts from moisture & shorting. The 24” cord allows me to place the plug through the radiator support, to the original location, below the grille, on the passenger side; and to store the receptacle end forward of the passenger side battery near the A/C charging port. The stock block heater is plugged in to one receptacle, and the battery charger AC side plugs in next to it. The 3rd outlet will normally be kept closed to avoid moisture & contaminants. The wiring from the charger is coiled and zip tied, making for a very neat & almost unnoticeable installation.

The Charger: I purchased a ‘battery maintainer’ type battery charger (http://www.walmart.com/ip/Schumacher-Electric-2-Amp-Maintainer/46167061 ) that is small enough to stow between the battery and the air filter box in my Gen 2 Dodge Ram 2500 & 3500 pickups. The charger comes with adaptors which include either ring terminals for permanent installation, or battery clamps for temporary use. I used the ring terminals, and ran wiring to both batteries so as to keep both batteries not only charged, but also warmed to prevent freezing, whenever the system is plugged in. (See below for details)

Charger DC wiring: I attached the DC output from the charger to the ring terminal adaptor, and attached them to the posts of the passenger side battery. (See Photo1a.2a,3a, & 4a)Here’s where I made one unwise choice, I wanted to charge & maintain both batteries simultaneously, so, I cut the ring terminals off, and connected wiring that would feed both batteries via a butt connector. (This was totally unnecessary, I could have just terminated both wires in ring terminals at each end, and used the same battery post connections as illustrated in photo # 4a ).

Additional photos and wiring diagram follows this post.

The wiring loom: I also bought a plastic wire loom (Harbor Freight http://www.harborfreight.com/1-4-quarter-inch-x-14-ft-protective-wire-wrap-66985.html enough to do both trucks with some left over) to protect and control the wiring that ran between the batteries. This is ¼” ID loom, and will easily handle the two 18ga wires.

I ran the wiring loom across the top of the radiator, and secured it in place with metal framed insulated clamps, (Fastenal Part No. (SKU): 0216763 ¼” ID, 10/$3.27) [in retrospect, I recommend using Fastenal Part No. (SKU): 0708767 the ½” ID clamp. @0.50/ea, as it’s a better fit for this application] https://www.fastenal.com/products/clamps?term=wiring+clamps&r=%20~|categoryl1:%22601 280%20Electrical%22|~%20~|categoryl2:%22601418%20C onduit%20and%20Accessories%22|~%20~|categoryl3:%22 601421%20Clamps%22|~
utilizing the same 10MM nuts that hold the battery cables in place. (note of caution: The bolts in the radiator of my 2nd Gen Dodge Ram pickups are a 'press fit', thus NOT solidly mounted. I pushed the first one down, and had a hard time holding it position while getting the clamp installed on that one)

Open the clamps up a little before installing them on the harness/loom, then close them as best you can before bolting them down. (Photo 5a) Use of the ½” clamps may work better, but, you may find clearance issues. Buy both and trial fit them, then return the unused version.

This was an off-the-cuff modification, done in a day, without much planning, due to incoming weather. You may have a better final product of know of a different method, but this works for my purposes.

Finally, once you are sure everything is hooked up correctly, plug the charger into the extension cord and observe for any sign of malfunction, fire, or nuclear mushroom cloud.