Battery post shims?

So went to drive the Abarth yesterday, the lights and dashboard lit up but when I turned the key, nothing and all power lost.  Tried a few more times, running late I drove the Crosstrek.

Looking after work, sure enough the negative battery cable was loose.  Guess it was giving enough for accessories but the starter was a no go.  I tried to tighten it but the clamp is completely together, no more tighty.  Just replaced the battery about a month ago.

I was thinking either deform the terminal with visegrips to a slight oval, or add some copper foil I have here at work.  But I looked up some Google just in case and see battery post shims made of lead.  Worth it?  Or just stick some copper foil in there?

Funny you should mention this. Was at Carquest looking for a negative battery cable. I like the ones with the molded on terminal. Seems they dont carry a negative terminal size, and suggest you just buy a terminal shim.

I went elsewhere.

I have had the same issue over the years on several cars and just last weekend with my truck, same issue as yours, had power but wouldnt crank, ground was loose at the battery and no more room for tightening. I have always just found something thin-ish and metal to shove between the terminal and clamp, this last time I used a short section of a worm clamp to jam in there.

Shave the gap down or replace the terminal, my local A1 carries crimp on connectors., not the BS bolt on ones. 

I've done the copper foil before. I wouldnt suggest long term but if you need to get home you can flip the cable over, since both are tapered you will be putting the small part of the cable clamp on the big part of the battery terminal. 

Another option is to make the slot bigger where you tighten the bolt.

I took a sheet of brass shim stock, cut a small segment out, wrapped it around the post and then tightened the clamp down. Works like a charm every time

I usually use aluminium soda can as shim stock 

File if you're can, shim if you can't!

I've done the copper foil thing a few times.  No problems, no failures.  Do that and don't overthink the problem.

You're way over thinking this.

Copper will work in a pinch but I'd shim it for the long term.

In reply to The0retical :

What am I looking at?!?!

In reply to rustybuckets :

A terrible idea. It showed up in r/justrolledintotheshop some months ago. I look through that subreddit when I'm having a bad day.

The terminal apparently broke/corroded then some genius used bailing wire and a pair of wood screws to secure the terminal back to the sealed box full of lead and sulfuric acid that produces hydrogen gas as a by-product.

I don't see how anything could possibly go wrong.

In the way-back, long time ago era, when I was broke as hell, using an actual copper penny as a shim after beating on it with a ball hammer to give it some curve worked great. I don't suggest doing that- just buy a new terminal. They're not that expensive.

I was a bit concerned about corrosion with copper foil, I'll either go that route or try the lead shims.

The0retical said:

In reply to rustybuckets :

A terrible idea. It showed up in r/justrolledintotheshop some months ago. I look through that subreddit when I'm having a bad day.

The terminal apparently broke/corroded then some genius used bailing wire and a pair of wood screws to secure the terminal back to the sealed box full of lead and sulfuric acid that produces hydrogen gas as a by-product.

I don't see how anything could possibly go wrong.

I gotta say, on the scale of 0-to-"Everybody-gonna-die!," that's some serious redneck engineering at play.  I like the strain relief of solid core copper wire on the cable and those screws do look to help hold the terminal in place.

That looks like the sort of temporary fix that was needed in a real pinch, and it just worked for a few years.  "If it's stupid and it works, it wasn't THAT stupid!"

I give that a solid 8 outta 10 Natty Ices!

I'd be half-tempted to roll up with that to an autocross tech inspection JUST to see the reaction :)

When I was a heavy equipment mechanic for a rock quarry outfit we had a mold tool and would melt some spare lead and reform the battery posts. Big battery’s aren’t cheap so we did whatever we could to save them.

In my military days while on deployments or field exercises I would use a self tapping screw or such in between the terminal and post. 

I've got two of these shimming the posts on my '99 Metro right now:

I would hate to have to remember how many times I've solved that problem with a pair of Channel locks & a little squeeze,

Remember the days when you just needed to use a bigger screw in the terminal when it got loose?

Additional edit-- 

Upon further examination, this particular image resembles a crucifix that would probably utterly fail in keeping the prince of darkness at bay.

If it's a lead clamp, I usually just smash it with a hammer. As it mashes down, the hole gets smaller. 

I've used the lead shims in the past, never a problem. Like $3 at Autozone. Just check the tightness when you check your oil but I've never had one come loose. At my work, we had small pieces of lead shim that we would use sometimes on the loaders and excavators

Take bolt out of the clamp and take a thin metal cutting blade in your grinder and “cut” the seam where the clamp is pressing together removing metal alowing the clamp to come together more. 

My 98 Eclipse has some sort of brass (?) shim on the positive terminal.  It looks factory.  I have used K&S brass strips as shims also.  But my father in law would use roofing nails...

rattfink81 said:

In my military days while on deployments or field exercises I would use a self tapping screw or such in between the terminal and post. 

Heck, I do that NOW.  Battery terminal ain't going to wiggle loose.

That’s the POSITIVE terminal with all that exposed copper. 

I’ve had a battery explode in my face. I feel fortunate to HAVE a face. 

I dont berkeley with stuff like that.