Rv battery melted and hooked up wrong?

[Gypsywagon]

So I bought an 89 1 ton Chevy Georgie boy with a 7.4L. It started and drove fine 2 hours. Started it regularly the first year or two, even drove it down the block but then it sat. Batteries went bad. It seemed to have new electrical work there too. So I get new batteries and go to put them in how I saw them and took pics too and it’s seems to be setup quite odd. The middle battery posts were melted too. Three batteries. Left to right goes pos neg neg pos pos neg. first. Pos goes to the second. But the two neg aren’t in parallel. That first to second then has a Batt line to a bolt (ground) on the frame with a bunch of newer wires to it. Ok I could see why that melted maybe? Neg was melted too on the middle battery which goes up to a solenoid. Of which there are three. The first battery negative goes to unknown at the back of the Rv somewhere I haven’t traded yet following the frame. The last battery on the right, pos goes to a solenoid, neg to top of motor I haven’t traced yet (cover inaccessible at the moment). This seems so odd to me. Anyone have any input? I don’t want to hook them up that way again if it caused the middle to melt. And that pos to a frame is wild. It probably 10 wires off it also. Including a drawing (b means batt label on solenoid, L means load). 24f to 24 and a 78 on the end. Thanks for any input, I’m not versed in Rv set up.

 

[Jim]

I would like to help you but there is too much missing info. The image you provided doesn't make any sense to me at all and my best advice would be for you to get a mobile RV mechanic to come over and look at it.

One thing for sure, the way those batteries are wired is not correct. It almost looks like one of the batteries (the one on the far right) was intended to start the engine, while the other two were intended to be used as house batteries. But this is entirely speculative and even if this was the intent, the wiring is wrong. And dangerous!

Please have someone come by and trace those wires to their intended end.

 

[NWIP]

Okay, first I believe one battery is your chassis battery and the other two is house battery. Are the batteries all the same voltage? Not sure from your drawing but suspect the one labeled R. We need a little more info

 

[Kevin D Pem]

The drawing is not enough. Pics would help here. You say grounding bolt, but is it an insulated post? Things could be the way they are supposed to be but like @Jim said not enough info.

Battery posts melt when connections to them are bad so even that info is not enough. Spend some time taking pics and posting them. Label the pics with numbers and put a number in a circle that shows what the drawing location is in reference to the pic.

 

[Buly]

Be careful and wear face protection. My neighbor had a battery blow up. Luckily, he was driving his golf cart at the time, and the acid was contained, but made one scary mess. If he was working on the batteries at the time, most likely he would have been blinded and burned.

 

[Gypsywagon]

Thanks so much for all the input. Apologies for lack of clarity. Yes I also deduced the right side battery is to start, as it goes to solenoid which goes to starter and grounds on motor just like any other vehicle. Which I can get it to crank, not start yet, with that. The other two and how the negatives are not connected to make it proper parallel and the positive to a frame bolt have me confused for sure. They are the same but with opposite posts so I wonder if they put the batteries in backwards. I’ve never had to use house batteries as always had electric hook up. But like I said the other set of posts weren’t connected together unless that doesn’t matter because they are grounded to the vehicle maybe? The post on the frame wheel well doesn’t seem to be insulated. It seems to be the type of bolt, I can’t recall the name, that has a square inset to lock it in without using a second wrench. I broke the bolt trying to replace a rusted through line to that positive post and had enough to extend it since it had a bunch of connections to it that could only reach to it and nothing else. I will be able to trace the line to the back later when I clear that area out to crawl under. I only took quick pics before I pulled them out to replace, also a new pic of where the lines would be but not connected.

 

[RandyB]

From what I can see, it looks like you have (3) 12 volt batteries. 2 for the house systems and one for the engine/chassis. I would submit that the wiring diagram should be something like this:

There's more to it all, but the basic battery cable connections should be in this arrangement to have 2 12 volt systems.

 

[Kevin D Pem]

After the pics I can tell you I would start over.