M38 Slow battery drain?

[joebuck]

I have a 52' 24 volt refurbished to original specs M38.. My batterys tend to slowly go down. I have just installed 2 - 12v trickle chargers on each battery. It s parked at my deer camp so i use it best every other week. Would rather address the problem.......any ideas on where to start? thanks

[wesk]

This is a common issue. Two sources are common.

1-Current leaking through a switch or accessory.
Standard troubleshooting means isolating one circuit at a time with a test lamp between the disconnected battery ground cable and the negative terminal of the battery closest to ground. As long as the lamp glows you have a leak to ground. When the lamp goes out you have finally disconnected the offending circuit/component. The usual culprit is a corroded or burned contact/s on the start switch.

2-Two batteries with non-conforming state of charge or potential.
This happens when you only replace one battery and now you have one tired older battery and one healthy new battery. When two dissimilar potential batteries are connected in series they become involved in a see-saw run down event where one chases the other until both are discharged.

If you do a search for the term battery you will find a dozen or more posts on this topic!

[joebuck]

Thanks Wes ,#2 is out , i bought 2 new batteries.

"test lamp between the disconnected battery ground cable and the negative terminal of the battery closest to ground. "

trying to grasp the above scenerio....so disconnect neg ground to frame..... then clip light to neg ground on frame and touch the lamp to the closet unhooked neg pole on the closet batery?

[wesk]

That's correct.

[regor]

I though to mention how I have handled this issue. After loosing 2 6v batteries on my 46 CJ (thru the key/coil switch) I now make it a practice to disconnect the negative terminal (I stick it on firmly) when not using the jeep. A manufacturer told me that a disconnected battery should maintain its charge (stands to reason). I continued to do this on my M38, disconnecting the negative terminal going to ground on frame. TIP: On my M38 I installed a switch that I purchased at an RV store (heavy duty) which turned the negative cable aforementioned off and on. I mounted it thru the fender well ahead of the right front tire which was adjacent to the negative cable going to the frame. It protruded about an inch and was painted 24087. (hardly noticeable) There is a red plastic key which is used to actuate. This also made it impossible to actuate the ignition from the normal switch on the dash. (theft proof)

[regor]

Wes, what is that little question mark in the little blue box under my name and the word member in my post? thanks!

[wesk]

Regor,

It indicates you have not selected a photo or emblem to appear under your name.

Regor,
The battery guy who told you they won't discharge if the terminal is disconnected is not entirely correct. The batteries will not discharge through the offending circuit any more but they can still discharge themselves several ways.

1-If left unclean with acid deposits across the battery case you can provide a circuit between the - & + terminals which will discharge the battery.

2-Flooded lead acid batteries will not hold their original charge over several years since there is always a very minute amount of internal discharging that occurs.

3-When two or more batteries are connected in series then as they age and their potential deteriorates at different rates they eventually will chase each other down as in a see saw affect.

[regor]

That makes sense, thanks Wes. I should have mentioned also that I keep
1 1/2 amp. battery minders on all my batteries (except the 6v, cause I haven't found one)