shimming a battery terminal?

Status
Not open for further replies.
Joined
Jan 4, 2003
Messages
3,203
Location
Southeastern, PA
Replaced the battery in my wife's car. I couldn't get the positive terminal properly tight, the clamp nut bottomed out just before the terminal cinched tight on the post. The positive terminal is one of those formed sheet metal jobs, so the old trick of hacksawing out some lead around the clamp nut is not an option. Also there's a couple of other wires connected at the positive terminal, so I don't want to replace the terminal. I took some copper foil, a few layers thick, the size of a postage stamp, and put that on the one side of the terminal. It seemed to tighten up and work. Should I go and get a proper battery terminal shim (I didn't know they made them until I looked just now) or are we "good enough"? Any thoughts?
 
I use tin foil in that type of situation.
I keep folding it in half and wrap it around the terminal,then loosen the clamp and slide it over as to not tear the run foil.
 
Originally Posted By: 901Memphis
They make slip over lead shims and sell them at places like auto part stores.

http://www.kmart.com/lynx-acces-lx-shims...2W005048328001P

http://www.autozone.com/autozone/accesso...ier=257147_0_0_


I use these on the positive terminal of my DH Platinum/EnerSys Odyssey to protect it from the clamp of my charger (I connect the negative clamp to a fender well ground point
wink.gif
).
 
I dug around and found some copper pipe, cut it down into enough to wrap around about 180 degrees and stuck it in there.

It wasn't exactly the right diameter but bent easily enough.
 
From experience, I can tell you that a bent penny works lot better than the store bought shims! They do sell the shims at store but in my case the taper of the shim caused the cable to slip off.
 
I've used a bit of lead/tin solder.
Using a dissimilar metal like aluminum or copper can lead to electrolytic corrosion..
 
If bent pennies work, how about a smashed penny out of one of those smashed penny machines you sometimes see at roadside tourist traps?

Fifty one cents per penny (you supply the penny).
 
How about just replacing the terminal on the end of the cable? Seems like the least "rigged" solution to me.
 
You don't want shims or anything that could cause a resistance. Car could draw hundreds of amps and even a fraction-of-ohm resistance is enough to cause a voltage drop sufficient to cause electrical problems. Every 0.01 ohms x 100 amps = 1 V drop: about 10% loss in battery voltage for every 0.01 ohm contact resistance.

Positive terminal is usually tightened to the positive battery cable by a nut. All you need to do is to get a $10 replacement terminal, remove the nut, and install the new terminal. Nut could be very tight though and you may want to use a large adjustable wrench as a vise on the terminal when you're trying to loosen the nut.

Here is how it looks for my car. 28800A positive terminal screws on to the positive battery cable with the 90179-08146 12 mm hex nut. The negative battery terminal is captive on the negative battery cable 28800B:

365234418.png
 
Status
Not open for further replies.
Back
Top