# Generator has no VAC



## Slow2go (Feb 5, 2020)

I bought a Champion Model 42432 brushless generator that's in need of repair. Previous owner bought it from Tractor supply as a salvage unit. He said he replaced the EXC winding capacitor which did not help (no change). I measured the capacitance of the cap. and it is labeled as 11uF and measures to be 10.9uF using capacitor check function.
I measured resistance of the winding attached to the cap and it indicated 7.2 ohms. Measured L1 to L2 and it indicated 3.9 ohms. I have not started the engine yet and have not disassembled the Gen. The unit is a 2017 model and looks new.
Would appreciate any help.
Thanks
Slow2go'


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## iowagold (Jan 22, 2020)

make sure all the wires are connected to the proper places!!
I have found over crimped and under crimped connections on these units!!
also check the breaker to make sure it is good...
low cost unit... low cost fast production!!

remove the spark plug,
check the voltage output at the ac socket while pulling the rope
see if you get any voltage. should be some low voltage.
if you have an analog or non digital ac volt meter that works best on the test!

that will let you know if the wiring maybe ok!

there is an issue with gens that they loose magnetics and you might need to re flash the units core..
mostly if they were dropped in shipping!!

if the wiring all looks ok...

check the oil and the fuel 
and start the unit to see if the engine starts..
then load it with a small 700 watt heater
after all this is a super small gen set!

I have seen several items from tsc that are ok!!
they are just returns from customers that do not know what they are doing or have buyer remorse and want to return as they bought the wrong item!!
you get that at Christmas!!
think ugly Christmas sweater!! lol!!
I would rather have the 5 bucks... GRIN!!


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## iowagold (Jan 22, 2020)

owners manual here
https://y79961nbs4u2hvbnwronx9zx-wpengine.netdna-ssl.com/wp-content/uploads/2017/08/42432-om-english.pdf
there is a parts list and wiring diagram.
and has the contact info for the company.

you might try this!
Flash Your Portable Generator with a Corded Drill




if nothing is broke it will work!!




another with a honda standard gen and a 12 colt jump pack





the drill works the best and is the safe method.
note make sure all connections are right on the gen before you do any of these methods!!


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## Melson (Dec 8, 2019)

I agree with iowagold, flash the field as a 1st step: With engine running apply a suitable DC voltage across the field windings.
A small 12 v battery is fine, just observe and keep the correct polarity. A momentary voltage application should result in output ac voltage.
Once the field has been regenerated it should thereafter be self-sustaining. 
However, there are certain conditions that could interfere with the residual magnetism necessary for field build-up. But try the field flash technique first, see what happens.


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## drmerdp (Apr 10, 2018)

The OP mentioned it’s a brushless alternator. Im not a hundred percent on this but... As far as I know they are self exciting and shouldn’t require the need to manually re-polarize the exciter.


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## Slow2go (Feb 5, 2020)

Slow2go said:


> I bought a Champion Model 42432 brushless generator that's in need of repair. Previous owner bought it from Tractor supply as a salvage unit. He said he replaced the EXC winding capacitor which did not help (no change). I measured the capacitance of the cap. and it is labeled as 11uF and measures to be 10.9uF using capacitor check function.
> I measured resistance of the winding attached to the cap and it indicated 7.2 ohms. Measured L1 to L2 and it indicated 3.9 ohms. I have not started the engine yet and have not disassembled the Gen. The unit is a 2017 model and looks new.
> Would appreciate any help.
> Thanks
> Slow2go'


Thanks much for your reply! I have now started the engine and attached Digital meter to the EXC winding wires at the plug connection in a piggyback fashion (all wires connected normal) I saw 5 volts and up to 14 volts varying, I then attached to the L1 and L2 connection and the voltage seemed to be roughly what I saw on the EXC wires. I have checked all connection and did not find any faults. I believe I agree with the friend from New Jersey that questioned flashing the brushless unit. I will try it though. Also I do not have an Analog meter, I wish I did! We are enjoying heavy rain right now so my experimenting might be delayed. Look forward to more
comments
Thanks again!


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## iowagold (Jan 22, 2020)

use the drill method!


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## iowagold (Jan 22, 2020)

check out this one!! it has a bad cap




yea not the same brand
but still loosing the stored energy in a brushless!!
change your cap again..
or test it with a good cap tester.
it could be partial out of spec..
11 uf seams low...
most are 30 uf to 50 uf…


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## iowagold (Jan 22, 2020)

humm the oem part is an 11 uf..
try the drill reflash.
drill plugged in to the gen
start the gen
pull the trigger on the drill
twist the drill in reverse.
it should come right up if it lost its charge on the cap..

and yes when you replace the cap you need to reflash!!


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## Melson (Dec 8, 2019)

drmerdp said:


> The OP mentioned it’s a brushless alternator. Im not a hundred percent on this but... As far as I know they are self exciting and shouldn’t require the need to manually re-polarize the exciter.


 @drmerdp, correct! I missed that; is what happens when I skim read.
That being said, you still need residual to energize the excitor rotor.

Good luck to the OP; I hope we hear how this is resolved.


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## Slow2go (Feb 5, 2020)

Hello again!
I have tried the flash technique as demonstrated with a had drill, I also used a 12vdc battery to attempt to bump the exciter/ capacitor circuit ( used an inline fuse to protect my "fingers". Nothing worked. I have pulled the rotor to inspect the resistor and diode that is shown on the schematic. The two windings were wired with identical parts a 14.7 k ohm resistor and a semiconductor device that I believe to be a diode.
I say, I believe it is a diode, because it has no markings that a normal diode would have (no cathode marker) and it is physically the size of a 3 amp diode. Resistance across the two "diodes" measure out as low resistance one showing 24 ohms and the other 39 ohms. I hope is that someone can confirm these devices are diodes. (I know that might require someone having experienced this same machine). Anyway I am surprised that they are so small. Oh yes; I bought an Analog multimeter and measured the field voltage and the output voltage. I saw 10 VAC
at each location.
Thanks for reading!


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## iowagold (Jan 22, 2020)

basic diode check with an analog vom high one way reverse the leads low the other.
the low should be 10-15 ohms and the high in the kohms.

try this video





this one has better id
and you can find the flow direction or the band cathode.





24 to 39 ohms sounds like a bad diode.
weak junction as they call it.

replace the diodes watch the direction they are installed...

wish you were closer so I could put eyes on it!

hey snap a couple of pix of the parts in question for us.


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