Smoking battery terminal, why?

[8N jdawg]

Good morning,

I had a rusty gas tank that was continuously plugging up my carb. Yesterday I removed the hood, dropped the tank, put a new one in, and then reassembled everything. Now I am watching smoke come off the negative battery terminal where the wire is on... no idea why this is happening after I mess with the hood and never touch the battery. Any ideas why this would be happening? After running the starter, trying to get the tractor to start, the connector is hot to the touch. Who knows what could be causing this?

 

[Russ from Dustville]

Good morning,

I had a rusty gas tank that was continuously plugging up my carb. Yesterday I removed the hood, dropped the tank, put a new one in, and then reassembled everything. Now I am watching smoke come off the negative battery terminal where the wire is on... no idea why this is happening after I mess with the hood and never touch the battery. Any ideas why this would be happening? After running the starter, trying to get the tractor to start, the connector is hot to the touch. Who knows what could be causing this?

Bad/loose connections heat up when current passes through them. I'd tighten the lug on your negative battery terminal.

 

[Jim.ME]

Clean the battery posts and cable ends to bright and shiny, then do it regularly to keep them that way. Inspect the cables for corrosion where the ends attach. The replacement bolt on ends can corrode where the cable is clamped.

Clean the other ends of the cables and attaching points as well.

 

[Jim L WA]

Hi Russ, welcome to the forum. It's true that bad or loose connections can heat up, but they don't heat up to the point where they smoke. Your problem started after you put the hood back on. Look for a place where a wire has gotten pinched and is making contact with sheet metal. More then likely the area behind the instrument panel.
Let us know what you found.

 

[Ray,IN]

Many people don't realize virtually all the end terminals are crimped on, thus air and water can enter. This can cause corrosion inside the terminal and create high resistance, which equals heat. If the cable ends are badly corroded, I replace the entire cable, JIC there is also corrosion under the cable insulation too.
When replacing battery cables, don't skimp on size either. I've seen many 12V cables used on 6V systems and the owner wonders why they're having issues.

 

[Woodtroll]

Does the battery terminal have only the one large ground wire coming off of it, or a smaller ground wire feeding the instrument panel or something, as well? If you have more than one wire, it sounds like you may have left the heavy ground wire loose after your work, and the small wire is trying to carry the starter load. Otherwise, check through all your connections to make sure they're clean and tight, and look for crimps/shorts, as already suggested.

 

[old]

Good morning,

I had a rusty gas tank that was continuously plugging up my carb. Yesterday I removed the hood, dropped the tank, put a new one in, and then reassembled everything. Now I am watching smoke come off the negative battery terminal where the wire is on... no idea why this is happening after I mess with the hood and never touch the battery. Any ideas why this would be happening? After running the starter, trying to get the tractor to start, the connector is hot to the touch. Who knows what could be causing this?

Smoke is common if you have poor connection and says things are getting hot. If you still have to old braided cable it maybe just be flat out wore out due to age

 

[Jim.ME]

Good morning,

I had a rusty gas tank that was continuously plugging up my carb. Yesterday I removed the hood, dropped the tank, put a new one in, and then reassembled everything. Now I am watching smoke come off the negative battery terminal where the wire is on... no idea why this is happening after I mess with the hood and never touch the battery. Any ideas why this would be happening? After running the starter, trying to get the tractor to start, the connector is hot to the touch. Who knows what could be causing this?

Another note. It is best if you give the details of the tractor/machine that you are working on each time you start a new thread. Often what is being worked on can have an effect on the answers you get.

If that post (positive, or negative?) was smoking they can also arc inside a cable clamp and damage the battery post and cable clamp. I have seen battery post melted away to the point the battery had to be replaced as well as the battery cable. While it used to be common, very few places will repair battery posts anymore.

If the connection was weak to begin with a slight bump of the cable near the battery, while you were removing the hood, could have been all it needed to lose the little contact it had.

 

[ChrisFromCLE]

A wise journeyman once told me that, “All electricity is smoke. The trick is to keep the smoke inside the wire.”

Many perfect answers above regarding good cables and cable ends and clean connections. This will be an easy fix for you.

Chris from CLE