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Discussion Starter #1
I've had the Gal in the garage for a few months. Was running fine when it went in. Today I hooked the battery back up and recharged it for a few hours (admittedly a sketchy recharger). Went to start it and at first it cranked but then, didn't.

All it does now is turn over very, very slowly, like 3 rpms.

The ambient temp is 70 degrees, the neg battery terminal is warm, the volts are 12.5, the lights work, there is a faint electric smell around the engine bay.

Next steps?
 

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Battery terminals can look clean but can build-up enough lead oxide to stop the car from turning over. Sounds like no direct amperage from battery to starter. Could be battery as well. Tried to jumpstart??
 

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Your battery voltage sounds low. A freshly and fully-charged battery will have a surface charge level higher than normal. 13 to 14 volts is common. Remove the surface charge by turning the headlights on high beam for 1 minute. Shut the lights off and test voltage, looking for 12.6-12.8V. Stabilized voltage on a battery that has been sitting one or more days should show 12.6-12.7V at room temperature. Charge level can also be checked by the electrolyte (battery acid) specific gravity, with a fully charged battery at 1.270, and a dead battery at 11.5V and 1.07sg. Just for reference, a 12.5V reading like you got indicates an 80% charge, if it was not a surface charge.

I would do a cranking voltage test, with the voltmeter attached to the battery terminals. Normal minimum is 10.5 volts within a 10-second cranking period. Absolute minimum is 9.6V in worst conditions. Do not crank longer than 10 seconds without a 1-minute rest for starter cooling. Bad test results mean a trip to test the battery.

However, if the voltage stays within spec during the cranking test, yet the starter is slow, that indicates resistance in the starting circuit, or a bad starter. Warmth anywhere in the system indicates excessive resistance, and warmth in the starter is normal, but in the battery, cables, and connections is not. Feel everything in the starting circuit (battery, heavy cables, ground straps and connectors) for signs of heat after cranking. Repair any warm spots.

Likewise, you can also use the voltmeter to find resistance as voltage drops, by connecting off each end of a singe cable (so you are also testing the connection), and cranking the engine a few moments. For example, probes to the battery (+) post and the starter relay post would test the cable and both if its connections. Any reading above 0.1V in any one section or in the relay is of concern.

Let us know what you find.

David

 

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Discussion Starter #5 (Edited)
This morning after leaving the lights on for a minute the volts were 12.67, at various spots around the engine bay. The bolt holding the starter wire to the starter seems stripped, I gave it some tightening but it still has a little wiggle in the terminal. I have a lever action quick disconnect on the neg. battery terminal that I hammered down after giving a good cleanup.

Went to crank and the motor again turned over, veeery slowly. As it was turni9ng, I saw smoke. It was coming from negative quick disconnect, from the solenoid and from the starter. Three places at once! The plastic lever on the quick disconnect melted some.
 

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I think your starter is toast
 

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Discussion Starter #7 (Edited)
Woo-hoo! She's running. I replaced the quickstart terminal but still got the same sloooow crank. Was just about to throw in the towel when it speeded up, and then started cranking for real. ten or fifteen seconds later, varrrroom.

After putting the tools away I tried it again and she fired right up. The car had been sitting there unstarted for a couple of months; I guess that had something to do with it but I don't know what.
 
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