Smoke on Battery's Red Terminal

rajthepilot

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My Snapper Pro 200XT isn't starting. I do hear a click. Battery is showing showing 12.49 volts. I'm also getting 12.49 volts from the battery side of the starter solenoid and the battery's ground. But when I crank it, I'm only getting 6.6ish from the starter side of the solenoid and the battery ground.

I would've assumed that I wouldn't get any voltage if the solenoid is bad. So why is there less voltage, because either the device inside clicks or it doesn't. I do hear the click. If I keep the mower key engaged, tiny bit of smoke begins to come out of the red wire where it connects to the battery's red terminal. I don't understand what is causing the smoke.

Is my issue just the solenoid or is there another issue as well?

Thanks
 

Rivets

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Dropping over 50% indicates bad battery to me.
 

Hammermechanicman

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Smoking at the terminal makes me think bad connection. If battery dropped to 6 volts with load applied it wouldn't smoke at a battery terminal. He said he measured the 6 volts at the starter side of the starting relay and ground. He needs to do a proper voltage drop test to determine if it is the positive side or the ground side or the battery.
 

Rivets

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I’ll agree that smoking is most often caused by poor connections, but readings of 6VDC indicates at least one bad cell in the battery. If he had a full 12 VDC it would smoke immediately.
 

rajthepilot

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Smoking at the terminal makes me think bad connection. If battery dropped to 6 volts with load applied it wouldn't smoke at a battery terminal. He said he measured the 6 volts at the starter side of the starting relay and ground. He needs to do a proper voltage drop test to determine if it is the positive side or the ground side or the battery.
I used a battery tester, which showed the battery is in good health. It's rated for 300 CCA, and the battery tester showed 295 CCA. When I check the voltage on the battery when cranking, it does drop to 7ish (which made me think it was bad battery), but then I used jumper cables with the car and it was showing 13.8 volts at the mower battery terminals when at rest, but when I cranked the mower engine, the voltage dropped to a similar number when I didn't have the jumper cables on.

I'll definitely change the solenoid, but I don't understand why there is tiny bit of smoke coming from the battery's positive when I keep the key pressed for few seconds. I also didn't expect the voltage to drop with the jumper cables connected
 

Hammermechanicman

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Anytime you have an issue with the starter (high current) circuit the first thing to do is clean and check both ends of the ground cable and both ends of the positive cable. Then start troubleshooting.
 
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