Dayton 4lm38b with generac rotor/stator no power output

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mjr46
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Chris wrote:
Mon Jan 27, 2020 7:01 pm
Next logical step would be to remove the 4 wire from the AVR completely and energize it with 12V while the unit is running, but this time leave the 12V on it. During that, measure AC voltage on the output at the breaker and also on the 2 and 6 wires (together, one lead on 2, the other on 6) and see what you get....
assuming i tested the right 4 wire...........it sparked and smoke started to arrise/melt the wiring insulation, i pulled it off when i saw that......now the wire i applied 12v to assuming the led is in upper right by the adjusting dial from there over to the right are the 6 pins 1 being the top i assume and numbered in sequence down to the bottom 6...right? if so i tested the 4th one down appling 12v to it and thus started to let the smoke out of the wire..lol.......tells me a short??
Chris
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Wow, not good!

The 4 wire should be the 3rd wire down from the top of the AVR or the red silicone insulated wire headed down to the brush assembly on the terminal strip. I would probably do an assessment of the wiring and make sure nothing is worn through, chewed, or otherwise damaged.

I would also remove both brush packs from the alternator housing and then test each slip ring to the rotor shaft itself for any resistance. With the rotor only and no brushes attached, you should read open from either slip ring to anything grounded or the main rotor shaft...
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murphy
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Maybe it is time to state the obvious.
A wire number is on the insulation of the wire. Its position in a connector is not related to its number.
mjr46
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murphy wrote:
Tue Jan 28, 2020 12:40 pm
Maybe it is time to state the obvious.
A wire number is on the insulation of the wire. Its position in a connector is not related to its number.
well that was not stated initially
mjr46
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Chris wrote:
Tue Jan 28, 2020 11:57 am
Wow, not good!

The 4 wire should be the 3rd wire down from the top of the AVR or the red silicone insulated wire headed down to the brush assembly on the terminal strip. I would probably do an assessment of the wiring and make sure nothing is worn through, chewed, or otherwise damaged.

I would also remove both brush packs from the alternator housing and then test each slip ring to the rotor shaft itself for any resistance. With the rotor only and no brushes attached, you should read open from either slip ring to anything grounded or the main rotor shaft...
looks like i'll have to retest tonight....because I assumed 4 wire meant 4th down on the regulator!
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Oh geeze, no! That would have been a dead short to ground! The #4 wire is literally the #4 wire. You should also re-test the other test with quickly bumping the 12V to the #4 wire which would be the RED wire at the terminal strip marked #4.
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mjr46
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Chris wrote:
Tue Jan 28, 2020 2:32 pm
Oh geeze, no! That would have been a dead short to ground! The #4 wire is literally the #4 wire. You should also re-test the other test with quickly bumping the 12V to the #4 wire which would be the RED wire at the terminal strip marked #4.
no worry...all it did was melt a little insulation.....i'll fix that later, i didn't hold it on long enough the other night to do any other damage, anyway i just tested the #4 wire with it all hooked to the avr and held the 12v from the battery on a lead to the 4 and boom!!!! the voltmeter went up to over a tad over 100 volts ......as soon as i pull the wire off it goes back to zero so looks like a excitation problem........so where to from here??? thanks for all the help chris!!!! i'm gettin' there slowly...lol like i mentioned i must keep the 12v wire hooked up for it to keep voltage output.....the moment i remove wire it goes to zero and then the led on the avr goes out then i hear a chirp from the rotor area and then the led comes back on dimly lite.
tbonini
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Did you retry the jump start test to see what happens. Put the wires back on the AVR and while the engine is starting up give the #4 wire a quick zap of 12V. You will see that spark again but shouldn't see any smoke. Does the gen continue to put out voltage?
mjr46
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tbonini wrote:
Tue Jan 28, 2020 8:54 pm
Did you retry the jump start test to see what happens. Put the wires back on the AVR and while the engine is starting up give the #4 wire a quick zap of 12V. You will see that spark again but shouldn't see any smoke. Does the gen continue to put out voltage?
yes, the avr was all hooked back up......i tried giving it a quick zap.....won't work until i leave it clamped on there and as soon as i remove the 12v wire...output stops.....this is all with the avr all hooked back up
Chris
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This could be two things actually. If the AVR isn't getting DPE power from the 2&6 wires when the alternator is making voltage, that would explain it. You should double check that when 12V is applied, you have AC voltage on the 2&6 wires (wire numbers not positions on the AVR) You could also have a bad AVR. In either case, I think it's also going to need a field boost kit...

Voltage Regulator: https://shop.gentekpower.com/products/g ... ulator-avr
Field Boost Kit: https://shop.gentekpower.com/products/g ... -upfit-kit
Generac tech for over 12 years. I'm here to help!
"The only source of knowledge is experience" -Albert Einstein
Looking for Generac parts? Gentek Power offers the full line of Generac replacement parts! Shop Gentek Power Generac Parts
A list of my favorite Generator & Electrical Tools! https://www.amazon.com/shop/gentek_power
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