How to Repair a Broken Battery Terminal Post on an Electric Golf Cart
We are able to drive golf carts on the private roads where we live. It's a great convenience for running down to the postal center or the clubhouse.
That convenience came to a sudden halt one day. I pulled into my driveway after a trip to get our mail and noticed that my battery meter was fluctuating on and off as I hit small bumps.
Well, that's easy. Something is loose, right? Probably just the clips to the meter. I pulled open the seat to take a look.
I felt around with my finger and found that one terminal was very hot. I could also feel that the nut was loose, so I went to get a wrench and came back to tighten it. I have to check these things every now and then; they don't usually loosen up, but I wasn't concerned. That is, until I found that I couldn't tighten it down with the wrench. It just spun, because the thread it was attached to was spinning loose in the lead of the battery lug.
How to Repair Broken Terminal Post
Follow these steps carefully.
• Remove battery (use strap if you have one).
• Disconnect battery cable.
• Drill pilot hole in battery post no deeper than 3/4 inch.
• Use appropriate size screw and washer to secure cable tight.
You can see what a normal battery terminal looks like in the picture to the right. There is a threaded lug that sits in a lead tab. That is what had come loose.
In the table above you'll find a summary of the steps I took to repair the loose lug. For more detail and photos, here is where I went to find instructions. It was obvious that these were the correct steps to take, but I was in a hurry and took some shortcuts. I'm going to go back and "do it right" before long, but I was able to get the cart going.
The problem was that I couldn't find my tap set. That's not something I use very often. I might have lent it to someone and forgotten about it, or maybe it just disappeared when we moved. For all I know it got sold at our yard sale along with other tools I thought I would never need again. Who remembers? Not me.
Secret Male Removal Methods
I called a poker buddy who lives up the street and asked if he had a set. He'd misplaced his also (I nominate tap and die set as the most commonly lost tools in our community), and suggested just setting a screw into the lead.
Lead is soft. Why not? Drill a little pilot hole no more than 3/4 inch deep (deeper and you'll be into the acid) and screw in a screw. Not great for maintenance, but it sounded like a plan. My poker pal drove down to help.
I have a lifting strap I bought from Buggies Unlimited. I think it would have been almost impossible to remove the battery from the carts without it. I highly recommend buying one of these.
Of course we couldn't easily disconnect the cable. There wasn't any way to grab the bolt to keep it from turning, so I disconnected the cable from the other battery instead and then pulled the battery to get it out where we could work on it.
We fussed with it for half an hour, trying various futile schemes. I even tried sawing it with a hacksaw. No luck. We finally gave up and I applied the time honored traditional secret male removal technique: brute force. I tore the damn thing out of the lead with my very angry bare hands.
More Broken Stuff
We were now ready to make a hole for the screw.
As I said, lead is soft. It's sticky when you drill into it, and that caused me to snap off my first drill bit. Fortunately, it didn't snap off flush, so we were able to grab it with pliers and coax it out. I tried again with a slightly larger bit and did it again almost instantly.
Sheesh. We were off to a good start!
I went one size larger, reasoning that would be harder to break, and handed the drill to my friend to let him have a crack at ultimate battery destruction. He managed to drill the necessary hole without breaking another bit. Later in the week when we were at poker and it came my turn to deal, I pointedly did not deal a game he doesn't like. My attempt at payback failed; he lost that hand anyway.
We found an appropriate screw and a brass washer of the right size and screwed that cable down tight.
Yeah, I know it will probably come loose but that might be some time from now. These batteries don't last forever, anyway. They say 2-7 years, with the longer life coming if you avoid discharging them fully between charges and maintain them religiously. I do that, so I might be good for another five years with some luck.
If it does come lose, I'll either put in a slightly bigger screw or try to find somebody here who still has a tap set. We can't have all lost everything we ever had, right?
A few days later I drove down to our garden to pick some squash. Imagine my delight when I got back in the cart and found the battery meter flat at zero. Of course I cursed myself for taking the easy fix and called my wife to come get me.
While waiting for her and kicking the ground petulantly, I opened up the seat to see how bad it was. To my surprise, the screw repair was holding firm. That wasn't the problem. Wiggling cables while watching the meter led me to the true source: the other battery terminal!
In our haste to put everything back and my joy at fixing the problem so easily, I had only hand-tightened the opposite, positive terminal, and had put away my wrench without ever snugging it down. That had worked loose from the comforting jolts of a golf cart suspension.
I didn't have a wrench with me, but I had my fingers, so I applied the Secret Male Brute Force Bare Finger Tightening Technique. This actually worked well enough to get me home—with my wife following, just in case. Once home, I tightened it down, still cursing softly under my breath.
For some reason my poker buddy thought that was rather funny when I saw him again the following week. Guess which game I plan to deal every time it is my turn?
It's been two weeks now and I have had no more problems. If I do, and can't find anyone with a tap set, I'll apply another Secret Male Technique that involves going to the store and buying an overpriced tool that I may never need again other than to lend to someone and then promptly forget all about it—until I do need it again, of course. But by then I won't remember who I lent it to.
I was driving back from picking some late tomatoes at our garden when a loud POP from under the seat startled me. A few feet later, the cart drifted to a halt.
The battery had blown, as seen in the picture to the right. No, not the post I repaired, the other post. I thought I must have been careless about pushing down on the cap after checking the water; bubbling hydrogen gas and a little spark paid me for my sloppiness.
Nope, that wasn't it. See bad cable causes expensive battery replacement for the real story.
That was a $148.00 lesson in battery maintenance.
I'll also have to get a new cable; the insulation burned away. I patched it with tape for now, but will need to pick up a new one.