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Hello all,
Got a head scratcher here. My battery is new, as is the voltage regulator, and generator's just been rebuilt by a pro I trust. I took pictures before taking things apart to make sure I put things back together correctly. After everything was back in, I polarized the generator in the prescribed manner. All seemed fine. A few days later, I came out work on a broken rear light, only to discover the new battery completely dead at 0.0 volts. I had an extra battery, so I put it in. The negative terminal sparked hard when I attached it, and with the engine not started and no key in, the Gen light is on bright. All other circuits seem fine, no smoke anywhere (thank goodness). Of course I disconnected the battery again. Advice? Answers? Ridicule? All will be accepted. Thanks.

Greenman Wood
'61 Apache 10, 235.

Your new regulator has a stuck cutout relay. Take the cover off the regulator and look at the contacts behind the Bat. terminal. They should be open. If they're stuck closed the battery will discharge itself through the generator. This usually ruins the regulator, and sometimes the generator as well. I'll bet nobody checked the regulator for proper adjustment after it was installed. On a 12 volt system the cutout relay should close as the armature voltage goes above 12.5 volts. It should open anytime the generator voltage goes below battery voltage. Some cutout relays stick or fail to open at the proper time as the engine is shut down, even on a brand new "Made in China" regulator!
Jerry

Although Chinese junk is probably more prone to sticking than OEM, it occasionally happened 50 years ago. I'm sure your regulator is ruined and the generator tried to motor and couldn't so it got hot. I have even seen wire harnesses burn in a situation like this. I always check the Gen wire at the generator for voltage when I install a new regulator, but it can happen with a regulator that has been in service for a while. I recently had it happen on my 64 Farmall with a Delco regulator that had been in service quite a while. I haven't gotten around to figure out what all got hot and I'm not looking forward to finding out.

Thanks, now I know what I'm doing as soon as the sun comes up...
Will let you know how it turns out.

Here are some steps to take.
1. Check battery water and general battery condition to
see if it will take and hold a charge....Load testing
may be necessary.
2. Check wiring for damage and make sure all
connections at generator, regulator and battery are
tight and free of corrosion.
3. Make sure fan belt is tight enough to drive
generator at full capacity.
4. Run engine at medium speed. Using a wire, touch one
end to regulator base and other end to a good ground.
If this corrects trouble, regulator is not properly
grounded anymore.
5. If test 4 does not correct trouble, make this test.
Connect a wire from regulator terminal marked "ARM" or
"GEN" to regulator terminal marked "BAT" with engine
running at medium speed. If charging rate increases,
replace old regulator.
6. If test 5 does not correct trouble, make this test.
Connect a wire from "FLD" Terminal of regulator to a
good ground with engine running at medium speed. If
Charging rate increases, replace old regulator.

If none of the above test show a bad regulator then
there is probably a problem in the generator itself.

There are basically two regulators supplied, they either come fron India and will usually have green writing on top of them or the "Made in the USA" regulator. Use the Made in US regulator or NOS Delco. The aftermarket made in US is expensive but well worth it. Made in India regs are JUNK and I wont sale them period. If you buy a non-made in US and pay a premium price your getting ripped....The made in US regs have it stamped into the mounting base.