Cleaning Car Battery Terminals

    Published: 06-16-2009
    Views: 45,623
    Automotive mechanic Scott Elbertson demonstrates basic car battery maintenance, including how to clean your car battery terminals.

    Scott Elbertson: Hi, I am Scott from the Automotive Service Garage in Alexandria, Virginia. I am showing you how to maintenance your car's battery. Now, let's move on to cleaning your battery terminals. First thing you want to do is of course, look at the battery making sure that where the terminals are oriented. Remember, your eye glasses and your gloves. I am going to remove the cover and take a look at the positive cable. We can see that there is a lot of corrosion around the positive where generally you get more corrosion than on a negative cable. So, let's proceed to be cleaning it. To do this we are going to need a 10millimeter wrench to remove the terminals. Remember, the negative terminal is always the first removed and the last reinstalled. Again, sometimes you need pliers to gently nudge the terminal away from the battery post. Place them away from the battery so you don't get accidental contact.

    Alright, now we have got the terminals removed. We can see that there is corrosion inside the terminal which we couldn't see before, but knew that there was going to be something based on what we saw around. So, again we are going to move the cable away so it can't make any accidental contact. We are going to work on cleaning the battery post themselves. First thing we do take a rag and clean off the excess. Now, we are going to use this modified wire brush. To the wire brush inside of here which battery post will go up inside of and make a nice, new, clean contact. As you can see that the post now is nice and shiny. They are made of lead so you can tell when they are clean and when they are dirty. The top of the post is slightly discolored. It's not a contact point so it's nothing you really need to worry about.

    Alright, let's move on to cleaning the cable itself. These are positive cable which we noted was the one that had the most corrosion. Now, take a rag put it down under so that there is no way that I may contact with the post while I am cleaning it. Now, there are several different products out there for cleaning battery terminals. This is the one I use which is a spray on and as you will see, it starts to foam immediately. What it's doing is neutralizing the acid that's on the cable itself and removing or softening most of the corrosion. Now, at home baking soda and water works good for this. You would actually take the cable. Use a small cup of some sort, something that you are going to reuse and douse the cable in it. It generally takes about ten minutes for this to happen. Now, if baking soda and water is not available, coco cola works great. Again, ten minutes with the cable in the end and you will be fine.

    Now, I am going to apply the cleaner to the negative cable. Let that soak. We sprayed the cleaner on and we can see that a lot of the corrosion has come off. What I am going to do now is I am going to take a small wire brush. I am going to go around the terminal getting off anything else that the cleaner didn't actually remove. Once we get that done we get everything loosened here I am going to spray them one more time just to make sure that I have got everything off. Terminals look good now. The positive is still bubbling a little bit, but we have got 90% of everything off of there which should give us a good contact. Now, we will start with the negative cable here. We will clean off the cleaner and as we can see the terminal has changed colors, which is indicating that the corrosion is all removed and we are down to the bare metal on the terminal.

    Now the positive post and that's look pretty good. If you noticed that I have used rags underneath of these battery terminals while I was cleaning them just to make sure that none of the acid that are removed from the cables were to drip down at any components in the car. You are wearing gloves and eye glasses to prevent that from getting on you. You certainly don't want any of these getting into any items on your car. Again, before installing we are going to use battery terminal protectors. We have cleaned them, now we want to keep them that way. The red terminal of course is going to go on the positive post and the black terminal pad on the negative post. Again, remember negative terminal is the last terminal connected. Now I am going to install the positive cable and make that we push it down so that it's oriented correctly all the way down at the top of the battery post slightly protruding through the terminal end.

    Last but not least, the negative cable. However, we got our terminals installed now we are going to seal them. It's battery sealer which you can get in an auto part store which will make a seal around the battery post even further preventing acid from getting on the post. We will move any covers that we took off to access the terminal and again look around to make sure that anything we have moved or any cables are oriented correctly. Now that I have showed you how to clean your battery terminals and put them back on, next we are going to show how to jump start your car properly.