Alternator or battery, 1994 Buick Skylark

The above car is the 6 cylinder.



About a eight months ago I came out to the car and the battery was dead. I bought a new battery because it was really old, then had the alternator tested and found out the alternator was OK.



Yesterday it was completely dead again. I jumped the battery and three hours later it was gone again; no turnover, no sound, no light, no nothing.



I don’t have a voltmeter and I’m wondering if there’s any way to tell if its the battery again or the alternator. The battery is from WalMart and I’ve heard stories about them, but I also know that their batteries are manufactured by a major company.



Any help is most appreciated

Almost any auto parts store can test the batter and the charging system, and you’ll soon know which is bad. I’m betting it’s time for a new alternator.

Don’t delay, because if your alternator is shot and you keep trying to drive the car you’ll ruin your 8-month-old battery, and that would be a shame.

I’d agree with others but if its a WalMart battery, take it in for exchange under warrantee. They will load test it first and if its OK won’t replace it. Otherwise you’ll get a new one. Nothing really wrong with WM batteries but I’ve had them fail in a couple years or last four. What I like is that you can get one 24-7.

Thanks folks. I figured this was probably the deal. One more question. I mentioned above that I can jump the battery; is it safe to drive to a local service center with it or will it die two blocks down the road? I’m trying to avoid towing costs.

Thanks again.

What you might do to forstall a tow, is to turn the head lights and inside blower on for 15 minutes with the engine running. If the engine is still running after that 15 minutes, turn the head lights, blower, and any other unnecessary load, i.e. window defogger, AC, seat heaters, etc. and drive to the local service center. You also could have someone tail you with jumper cables to recharge the battery if the alternator isn’t charging the battery. Drive in the right lane during the day and you will probably be okey.

GM vehicles have those problematic side terminal battery connections. Corrosion often builds up undetected under the boot of the positive cable end, between the two conductors. All sorts of electrical gremlins can ensue, including failure of the battery to charge properly.

This is an interesting point. Can you offer a suggestion on how to take care of this? It sounds like something I can do in my parking lot; I’ll have another vehicle I can use to jump it so maybe if I can fix that I can get the battery to charge again.

Thanks so much.

Disconnect the negative connector first, then the positive. Pull back the rubber protective boots and check for corrosion. Using a wire brush, shine up the ring terminals. There should be two for the positve cable; make sure to clean both sides of both rings. Reinstall, starting with the positive connector, then the negative connector. I think the job requires a 5/16" wrench for the bolts. Pretty simple, and worth doing even if it doesn’t solve the problem. Also check the connections at the other ends of the battery cable, especially the grounds.

The battery may not be charging at all, now. In which case, you wouldn’t get anyplace. If you must drive it, get a jump start connection. Keep the donor vehicle connected for 20 minuets to partially charge the battery. Disconnect the jumpers, and drive directly to where you need to go.
You could replace the battery cables. Walmart has cables in their automotive tire section. Measure the length of your battery cables before going to the store; or, take the battery cables off and take them with you for comparison. Put the new battery cables on, do a jump start and let it idle for a few minuets. If it continues to run, drive the car to an auto parts store for testing of the battery and alternator (a free service), or a service center of your choice.

One way to roughly check the alternator is to jump start the car with a dead battery and see if it runs. If the car continues to run, there’s a good chance the alternator is charging otherwise the ignition couldn’t fire. This does not guarantee that the alternator’s diodes are good or not. A bad diode in an alternator is a frequent cause of discharged batteries that were otherwise charged.

If you have a volt meter, you can check the voltage of the dead battery. It will likely be just over 12 to as low as 11 volts. Once you start the car check the voltage again and it should read closer to 14 volts.

One thing I noticed about our local Wal Mart’s batteries last month when I went to get a battery for my tractor was the age of the batteries on the shelf. I pulled 4 batteries the size I wanted from the shelf and the newest one I came across was over 10 months old. One of them was closer to 2 years old. I didn’t buy that garbage. There’s no doubt in my mind they’ve been sitting on the floor in the back for a long long while. Batteries have a sticker on them with a letter and number. The letter is the month it was made and the number the year. The battery case is also stamped with the manufacture date in the same manner. Always make sure you get a current month or 2 month old battery.

If you alternator proves bad, I suggest having it rebuilt. The alternators you buy at any parts house are not new, they are remanufactured or rebuilt and are priced like they were new. The last one I priced was over $200. Rebuilding the same alternator cost me $45. Most towns have a starter/alternator shop. You’ll have to remove the alternator and take it to them. Generally, you can drop one off in the morning and pick it up in the afternoon. My office happens to be near one, and I’ve been known to pull an alternator when I get there, walk it over to the shop, and then pick it up and put it on to drive home in the evening. About the only difference between them doing it and you buying a rebuilt in the store is it doesn’t come in a box, and normally they don’t take the time to put the case in a tumbler to clean it up. Reliability is pretty much the same.

Skip

One thing I forget to mention and now I feel like an idiot. When I jumped the car the other day and got it started I DID NOT have an alternator light. I don’t know if its working but when I jump the car again I’m going to turn back the ignition key so I get all the lights to come on so I can see. I was told that if you don’t get an alternator light that its probably the battery. Is this correct?

That’s a simple rule of thumb. A charging system check will definitely determine of the alternator or battery is bad. The test will add a load to the charging system, and determine if all components are within spec. I’ve seen an alternator go bad, but not turn on the charging light. This can happen with a bad winding, and charging capacity is compromised.

Friends,

Thanks for the replies. I really appreciate it. Problem was solved. It was a defective battery and bad connections. Alternator was OK, even though the light was burnt out. Battery was replaced with an Insterstate and the connections where changed. Thanks again!

Paynow, I’ve had 2 walmart batteries in 10 years which is really good life for a battery. It is neither the battery nor the alternator. Just make sure the battery terminals are really clean and properly tightened - not as tight as you can get them. Anyone can dust off the corrosion from the terminals but very few people can scrape the electrical crust (which is not always visible) off of the contact surfaces. Scrape the contact points with a screwdriver or knife blade and you will see what I am talking about.
If it was anything else like a serious voltage draw from some component you would have very different manifestations before total failure. Anything rangeing from noise to sparks to blinking lights when going over bumps.

Norm,

Thanks for this. The mechanic who did the work cleaned off the connections; they’re the ones who told me the battery was bad. Maybe I got hosed; I did some research though and was told these guys are very honest. They did what you just mentioned.