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The battery is not charging. I have the ignition fixed and operating properly. Now my battery does not charge. The battery is an odyssey per the plans. It is about 10 months old. I found a ground to the engine block loose and repaired it. Then charged the battery and flew for an hour today at 2900 to 3100 rpm. There was a constant drain. I do not have a fuse on the charging circuit and checked all the wires for proper connection. I have good crimps and no broken wires. Could I have a voltage regulator that has gone bad? To be honest I did accidentally short the positive on the battery as I was hooking it back up a while back. But it did charge after that it was showing 14v on the EFIS. There is no noise coming from the back of the engine when I hand turn and I did all of the service bulletins and used the correct loctite and primer where noted.

The charging system is pretty simple, so there are generally few things it could be.

1. The stator itself is shorted out.
2. The voltage regulator is bad.
3. The battery is bad.
4. The wiring has a break somewhere, or the wires got crossed during a reconnection.

As I think you alluded to, my problem was with the ENTIRE alternator system, and even then it produced a charge until its very last breath.

I found VERY little in the way of useful information on testing a voltage regulator is you are not willing to do it under load (prop spinning, multi-meter hooked up to the alternator leads). Here are some of the links I found:
Stator:
https://www.youtube.com/watch?v=G_7FD_ZhKSg

From Sonex Tech Support:
"Unless you are willing to meter the output voltage on the aircraft {I indicated I didn't like working around spinning propellers}, the only other option you have is to apply up to 30 volts AV to the input and measure the output voltage.
If it is the stator, that should output up to 30 VAC at full throttle.
You should also be able to probe the output wires of the alternator and read almost no resistance. If you have resistance, then the stator is the likely problem."

Voltage Regulator:
http://www.ehow.com/how_8071010_test-jo ... actor.html
And... "The rectifier/regulator contains the diode. If I recall correctly, you can unplug the alternator from the rest of the charging system, and connect an ohmmeter across both alternator leads. If you have an open circuit, your alternator is bad. If the circuit is closed, there is one more step: Connect the ohmmeter across one of the alternator wires and ground. If you have an open circuit, it is good, if you show continuity, it is bad."

Thanks Mike,
I will test continuity of the stator tomorrow. I can't do the load test since I don't have help. But the other tests will help eliminate some things. I don't mind just paying for a new voltage regulator and replacing in lew of a test.

I went to the hanger this morning and tested the two ac leads coming off of the stator and there was continuity. Then I checked each ac lead to ground separately and there was no continuity. Since I have no helper and work alone. I put wires with bare ends into the ac leads and plugged them into the regulator to hold them. Then ran the wires into the cockpit and taped the other bare end to my voltage meter. Now I can test the output voltage of the alternator from inside the cockpit. Started the engine. Since I could not tie down the plane I ran it up to 2000 rpm and got at least 20 volts AC. It should put out 30 volts AC at WOT. That proved that the alternator was good. I sent a note to Sonex with my test results and they agreed that it must be the regulator. I was able to locate one close to the airport and installed it. I test ran the engine and confirmed there was a charge. I put the cowl back on and went for a short flight to see how the voltage was during WOT operation. The alternator is charging now. I know this because I saw the voltage go up with RPM like it did when the other one was working correctly.

I forgot to mention I added a ground wire from the ground block to the bolt holding the regulator to the firewall.

That's good news. I'm glad you were able to locate a regulator close to the airport--makes the prospect of getting stranded somewhere due to a voltage regulator problem seem a little less likely.

gammaxy wrote:That's good news. I'm glad you were able to locate a regulator close to the airport--makes the prospect of getting stranded somewhere due to a voltage regulator problem seem a little less likely.

I have an extra one I ordered from Sonex, just in case! It's in my tool bag in the plane, along with a lot of other things "just in case."

I'm going to order another one from Sonex. To keep on hand.