Battery draining

I'm having a problem with my Mighty Mite. One of my batteries keeps draining and not getting recharged when I run the engine. I've replaced the battery with a new one and the same thing happened. It's the battery that has the positive lead to the starter. There aren't any shorts or breaks in the cables.

Could my generator or voltage regulator be going bad? I did adjust the tension on the belts to the generator because they seemed loose. This didn't help. Should there be more play than 1/2" in the belts?

Any help would be appreciated. NAPA is probably getting tired of me returning batteries.

Get some voltage measurements when the engine is running, there isn't much to go on here.....
You should see 28 volts across both and 14 across each individually when charging (plus or minus a fraction).

Get some voltage measurements when the engine is running,

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Thanks Bjorn, I'll try to get that today. Have to push it out of the garage so I can jump it with the M1009.

The batteries must be identical when used in series like this, make sure they are the same brand and age.

Bjorn,

Not having identical batteries will make that much of a difference? Mine are definitely not the same. I did have two of the same when I got the Mite but they lost their charge in the cold weather here. I replaced them with what was available from NAPA and as you know, you can't always get good parts or service where I live. Looks like I will have to bite the bullet and get the 6HN batteries in the next month or so. I just don't want to spend that kind of money only to have them drain on me.

Well you don't have to have the 6HNs, just get two cheapes from NAPA, as long as they are the same. Different internal resistances will effect the charging.
Do you have a 12-volt charger? Charge each individually and go from there.

Yeah, I remember the NAPA, nice to be able to walk to the store.

What does Bruce have on the laundry trailer?

Once you find the cause of the "leak", put a solargiver on the batts, it will help them have a longer happy life with desulfated plates.

What does Bruce have on the laundry trailer?

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I think there is only one battery on the laundry trailer. It may be a 24 volt. It's really big. I'd have to go out and check. The sun is just coming up over the mountain so it is still a little dark out.

Yeah, I remember the NAPA, nice to be able to walk to the store.

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Bjorn, The NAPA is in the next town over, 80 miles one way. We have a CarQuest but the batteries I have came from NAPA. No reason to buy new batteries when I can exchange them for free. Our hardware store is a NAPA dealer but they have limited supply and won't take batteries for exchange. This is when it sucks to live in a small town. I'm looking forward to being in NJ at the end of the week.