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New battery = huge sparks flying !!

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Old 07-16-2017, 08:54 PM
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drewsky
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Default New battery = huge sparks flying !!

Have an interesting situation. My 65 has been sitting in the garage for the hot summer. Battery died from
the heat and not starting it for 3-4 weeks with the rally pack clock running. I can charge the battery and start it up with no problem. This morning I went to Walmart to exchange it (yes I know this is problem #1) for a new one and when I went to hook it up the time I connected the ground terminal huge sparks were flying ( like as if you dropped a wrench across the two terminals) and the car launched forward a foot because it was in gear and almost knocked me on my ***. It took a chunk out of the terminal it was so bad. I took the car out of gear and just barley touched the terminal and it was more fireworks.

Ok ok so I found a battery I had that was half dead and charged it up. It wasn't full power but when I put this one on no issues at all. Just very small normal blue tiny zap. Open the door and lights turn on and cranked right over with power and fires right up. The battery isn't brand new but has enough to start the car with no problem.

Took the new Walmart battery and strapped it back on and same problem! Blew another chunk off the terminal. So here is what I am thinking, either the battery is wired backwards and or has another serious issue. Or my Petronix ignition and or ignition switch under dash has a problem. There are no blown fuses by the way. Has anone run into an issue like this at all?? Did something kill the battery in the first place you think? Is there any way to test something like this. I ran the trick Of connecting the positive terminal and not the neg then touching a light tester to the negative terminal to the disconnected cable and the light did light up, but I can touch it to almost any metal under the hood and it lights up.

Last edited by drewsky; 07-16-2017 at 08:57 PM.
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Old 07-16-2017, 09:30 PM
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Gun Jam
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so with the older battery it was fine and started up?

That is really odd.. I would suggest checking polarity with a multi meter. You have 12V running straight to ground because you've got the wires hooked up backwards despite what the colors may indicate.

Do you see a physically stamped + on the battery?

I suspect its possible that a lead acid could be charged backwards??? Im not sure on that but its possible

You need a multi meter to figure out which way is really +.

The multimeter will show -12v if its backwards and 12v if its good to go
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Old 07-16-2017, 09:59 PM
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DRAGUL
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I think you shorted the start relay trying to start it with the old battery. The contacts could be stuck together, and that is why the car jumped forward when you applied power. The starter draws a lot of amperage, so you would see a lot of sparks if you are connecting the cable with it engaged,
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Old 07-16-2017, 10:11 PM
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drewsky
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My initial thought was the battery was wired backwards! I am 110% positive I hooked them up correctly.

As as far as shorting the relay? What would fix this? A new syniniod that the pos terminal hooks to along with the alternator wires?
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Old 07-17-2017, 12:19 AM
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Gun Jam
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Tried wally battery got fireworks

I thought you said that it ran okay once you put the old battery back in?

Tried wally battery 5 min after it just ran fine and got fireworks again


So Drewsky if you are 110% sure polarity is correct that means you put a volt meter across the terminals right? what did it say?

The start relay is a good theory and I was going to suggest that directly until you said that the old battery worked great and every time you try the new one you've got issues.

im sure you've verified that visually its correct. But did you really look at it mechanically and verify the actual electrons are doing as you suspect? normally its whatever try it and see. But you are literally dealing with a 1,000+ amps of unregulated current flow. The more scientifically you can approach this problem the less potential you have for bodily harm and parts damage.

If you checked with a volt meter and you are 100% sure you know which way the electrons want to go. Then next take an Ohm reading across the heavy leads on the start solenoid the ones on each side you should see very high resistance (10+ mega ohms) or equivalent to an air gap. If you see very low Ohms like 1 to 100 that means the solenoid is closed and would be as DRAGUL suggested.
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Old 07-17-2017, 12:47 AM
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I like the mislabeled wally world battery theory. It wouldn't take much for this to happen, just the wrong sticker on the battery (there's a reverse terminal version of the proper battery that's very common). Stick a voltmeter on it to find out.

If it sparked during install but the old battery works fine, either the battery has problems, or you're doing something different during install of the new battery.
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Old 07-17-2017, 01:11 AM
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"I suspect its possible that a lead acid could be charged backwards??? Im not sure on that but its possible"


Er, no, not possible. The chemical reactions in a lead acid are such that juice flowing OUT always weakens the acid, and juice flowing IN always strengthens it. No other way. To push energy BACK into a battery requires a voltage slightly higher than the battery's own voltage, regardless of it's state of charge. This is why a vehicle during operation has an operating system voltage ALWAYS a bit higher than it's battery voltage, to prevent the battery from contributing any energy to the operating system. Meaning: battery starts engine, then becomes a boat anchor. Once started, everything electrical is run by the alternator.


I believe the post mentioning stuck contacts is likely right on. Thus, as soon as juice was available to the starter, the car lurched forward. Good testament to keeping everything in Park or Neutral, while working, eh? imp
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Old 07-17-2017, 01:29 AM
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drewsky
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Originally Posted by Gun Jam
Tried wally battery got fireworks

I thought you said that it ran okay once you put the old battery back in?

Tried wally battery 5 min after it just ran fine and got fireworks again







So Drewsky if you are 110% sure polarity is correct that means you put a volt meter across the terminals right? what did it say?

The start relay is a good theory and I was going to suggest that directly until you said that the old battery worked great and every time you try the new one you've got issues.

im sure you've verified that visually its correct. But did you really look at it mechanically and verify the actual electrons are doing as you suspect? normally its whatever try it and see. But you are literally dealing with a 1,000+ amps of unregulated current flow. The more scientifically you can approach this problem the less potential you have for bodily harm and parts damage.

If you checked with a volt meter and you are 100% sure you know which way the electrons want to go. Then next take an Ohm reading across the heavy leads on the start solenoid the ones on each side you should see very high resistance (10+ mega ohms) or equivalent to an air gap. If you see very low Ohms like 1 to 100 that means the solenoid is closed and would be as DRAGUL suggested.
I exchanged the old Walmart battery for the same one. The battery i tried that started the car and did not make fireworks was an older smaller "not correct" battery I had in my shed. It did enough for the t est and started the car with no issues at all. So the real question is , is the new battery backwards or is it a syniniod. The part that is confusing is the other older battery works just fine. I can not find my volt meters since I have moved to this new house and . I'll have to get a new one to verify this 100%
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Old 07-17-2017, 01:37 AM
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Gun Jam
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ehh. Im no battery scientist but I might bet say 10 bucks that it could happen IF..the battery were totally discharged and then recharged backwards or during assembly when it had no charge state it could be charged backwards... Im about 10 bucks sure this could happen...do I think its the issue? ehhh welll.... considering the danger here of catching molten lead to the eye or burns why not check? its easy. A reversed label is more likley

Im on board with the stuck solenoid too but that theory has a few holes punched in it because right after it threw sparks with the wally battery it acted just fine with an older battery he had...It ran good. He tried the wally battery again and yeah sparks...That Theory holds water but its leaking out quickly if its correct you'll have to find the patch for that hole.

I am WAY on board with as much testing as possible before smacking that battery cable across that terminal again.

Last edited by Gun Jam; 07-17-2017 at 01:47 AM.
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Old 07-17-2017, 01:43 AM
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one thing you can try if you are missing your volt meter is to take a small gauge wire like 18Awg something that you might find for a small electric appliance maybe a motor wire for a hair dryer or something. Strip off a bunch of insulation and wrap it around the post and then touch main ground wire to the little wire. if there is still an issue that little wire will burn up and act as a resistor preventing a massive discharge of current and damaging posts and terminals.
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