Melted Battery Terminal

Lin · February 11, 2013, 03:11:47 PM

This is the first time I have seen this. I went to start the bus up for the first time in about a month. It would not crank and then everything went dead. I opened the battery compartment and found that the positive terminal on the top battery had melted half away. There were little solidified puddles of lead around it. Has anyone ever tried to repair something like that? My inclination is to buy another battery.

chessie4905 · February 11, 2013, 03:56:36 PM

You could rebuild the lead back up with a large soldering iron, but don't use a flame, unless you know what you are doing or Kaboom. Sounds like the connection was poor, battery,s were low or trying to start with a really cold engine with long cranking times, or both. This was a problem with the Olds diesels if that was done. On them it would first show up as loosened terminals, as the lead on the side terminal batteries would relax under the heat generated and relax the terminal tension. Eventually it would degrade to burned terminal and deteriorated side post.

Boomer · February 11, 2013, 04:04:41 PM

A new post can be poured by a battery shop.

Bussman84 · February 11, 2013, 07:15:07 PM

I had a loose connection on one of mine and it did the same thing. Took it out and took it to my local interstate dealer (not even an interstate battery), and they poured a new terminal on top. Said they couldn't warranty any part of it of course but on the same note didn't charge me anything for the repair either. Told me to be careful tightening the terminal and to remember them when it was time for a new one!

Still holding together, so far so good!

Billy

eagle19952 · February 11, 2013, 10:47:39 PM

I have poured a few, it is easy,take a short screw,run it a 1/4 inch into the remaining post. then make a mold from a piece of tin can,squeeze to shape with a vice grip, melt lead and pour.
old tire weights, lead shot fishing weights...

cool and file/taper to fit....

Lin · February 12, 2013, 10:57:29 AM

Seems worth a try. It is not the top that melted off. It is more like vertically cut in half. I saw some metal terminal post covers at a parts store recently. Maybe I will get those, cut the top off, put it in place and fill it with lead (as the cowboys used to say). Thanks for the info. Although it is new to me, I am now told that it is pretty common with gold carts since they have so many connections, and it only takes one lose one to melt a post.

gus · February 12, 2013, 02:42:25 PM

Lin,

Just by accident I found that batt posts and clamps slowly build up a thin black coat of corrosion. This happened to me quite a few times before I figured it out. This thin coat will shine up nicely, even when cleaned with one of those wire brush things, but it is a false shine. It is actually shiny corrosion.

Of course this corrosion increases resistance at the poles and causes heat when cranking vigorously.

This takes about a year or so, depending. I now remove all my clamps once a year and scrape, not brush, down to shiny lead, add a small amount of Corrosion X, and re-clamp.

I'm not saying this is your problem, but it may be a contributor.

It doesn't take much resistance to really heat up posts when cranking large engines.

Lin · February 12, 2013, 04:32:12 PM

Hard to say what was the cause of the bad connection, but corrosion buildup is a good candidate. Using a lug connector as a molding, I ended up pouring some lead in after trying to fill it with solder was turning out to be slow, messy and wasteful. The pour worked better than I thought it would. I bought some battery terminal shims and used one there to hopefully hold things together. I will just have to watch that one.

gus · February 13, 2013, 02:01:27 PM

The problem with solder is the metal it attaches to has to be hot enough to melt the solder, otherwise there is no way it will attach to anything.

Poured lead does not have this problem, it just flows into all the nooks and crannies and attaches itself mechanically if not chemically.

Jnbroadbent · April 21, 2013, 10:03:05 AM

This might be old but this also happened to me, terminal melted half off. Here's what I did the other day

Cut off terminal (keep this) so it was flat. Carefully drill 1/4" bit 1/2" down. If you go to far... battery acid

Tapped it with a 5/16", took a 5/16 brass screw, put it in (be careful, lead is soft, easy to strip) I had to get the rest of the screw off.

Made a cast out of some 3/4" wood, drilled a hole, cut that in half and clamped it together so when it's done I can just pull it off the side rather then up. (which won't work cause it's easy to overfill) You can put some silicon caulk at the bottom of the terminal (on the battery) so the lead doesn't run.

Melted the rest of the terminal with some old terminal clamps, scraped off all the crap that sits on top, poured it in, let it cool, pull off cast, and file.

I take no responsibility of you screw up.

Lin · April 21, 2013, 12:13:24 PM

So far my fix is holding up.

pvcces · April 21, 2013, 11:01:16 PM

One more thing; that black shiny coating only forms on the positive post. It is quite hard and a wire brush will likely not remove it. It is either a very poor conductor or not a conductor.

For me, sandpaper was the best for removing it. Be sure to avoid black sandpaper as it is a poor conductor and will cause hot spots. Paper with a purple cast is aluminum oxide, a good choice.

Tear a strip about 1 inch by 4 to 6 inches off and use a shoe shine motion and you should get a good connection.

Take care.

Tom Caffrey