# Odd Champion Generator Problem



## zhaarnak (Jul 26, 2021)

I have been attempting to get a friends generator working but the darn thing is being a pain in my rear. The generator is a Champion model 100165 Dual-Fuel. The unit quit running a few years ago. I am attempting to get it up and running so his children have a back up generator as they are totally "off the grid".
The first thing I did was give her a shot of ATF to lube the rings, check compression (it was very good), checked coil output (OUCH!), cleaned out the fuel tank (not too bad), screwed in a new plug, dropped the carburetor bowl (found a little bit of sludge), cleaned out the main-jet, blew cleaner through the passageways, checked the fuel shutoff solenoid (dang, it works, surprise surprise), gave her a shot of gas, and gave her a pull. She fired on that first prime, but now the issues began. She will only fire when primed. 

I removed and cleaned the carb again (including the idle jet), reinstalled, no improvement. Checked the Low-Oil shut off sender lead at the crankcase, it was not grounded. Unplugged it anyway, no change. Checked for spark again (used a spare plug this time) darn thing has a heck of a spark. At this point I just knew it had to be the carburetor, so I ordered and installed a brand new one. Same problem. I even removed the new carbs fuel shut off solenoid (Pesky things), blocked the hole, and tried that. With the choke fully on, she will fire for a second (like when primed) and then die. I am beginning to suspect that it never was a carburetor problem, it is a electrical problem. I am guessing here, but could it be that the generators voltage is climbing and then it goes into an overvoltage condition and shuts down? I ask this because it appears (in the wiring diagram) that both the ignition coil and low oil level circuit appear to be tied into a module that Champion calls a VFO Diode. Interestingly, Champion's gasoline only generator of the same wattage lists this module as a Over Voltage Protector. Also, can anyone here tell me just what the function of the microswitch located at the gasoline/propane selector lockout slide is for?

Any help would be greatly appreciated! THANKS


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## Browse Deweb (Jan 16, 2021)

Could be a vapor lock problem with your fuel delivery:


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## drmerdp (Apr 10, 2018)

You should get a spark tester. Check if spark is the first to cut out or if it remains sparking as it shuts down.

Will it remain running if you keep spritzing the intake with starting fluid?


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## zhaarnak (Jul 26, 2021)

I thank you for your replies! 
Browse Deweb,It does not appear to be vapor lock. I am getting good fuel flow through the new carburetors bowl drain. 

drmerdp, I am going to put my timing light on her and check to see if the ignition cuts out. Giving her a spritz of gas or starting fluid after she cuts out after building RPM has no effect. This, plus the fact that she WILL fire again, when primed or choked AFTER a couple of seconds of 0 rpm. This is why I am thinking the issue is electronic, possibly due to overvoltage shutting down the ignition? I did disconnect the low oil sender lead and this had no effect.


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## iowagold (Jan 22, 2020)

could be a bad coil or a bad shut down switch.


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## drmerdp (Apr 10, 2018)

zhaarnak said:


> I thank you for your replies!
> Browse Deweb,It does not appear to be vapor lock. I am getting good fuel flow through the new carburetors bowl drain.
> 
> drmerdp, I am going to put my timing light on her and check to see if the ignition cuts out. Giving her a spritz of gas or starting fluid after she cuts out after building RPM has no effect. This, plus the fact that she WILL fire again, when primed or choked AFTER a couple of seconds of 0 rpm. This is why I am thinking the issue is electronic, possibly due to overvoltage shutting down the ignition? I did disconnect the low oil sender lead and this had no effect.


Timing light should do the trick. Ignition coil is the likely suspect.


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## exmar (Jun 29, 2015)

Agree that it sounds like electrical issue, watching spark will give you a direction to proceed. You mentioned cleaning out the tank, what about replacing the fuel line and filter? I've found that when bringing back a small engine that wasn't "laid up" correctly, all kinds of interesting sludge and particles form in the fuel circuits. Rebuilding carb, replacing carb and a small piece of crud suddenly becomes ambulatory and you're back to where you started. 

You mentioned "gave her a pull" and later talked about the fuel solenoid which needs full 12V from the battery to operate. Was the battery charged? You further mention removing it and plugging. I've only replaced them, usually when eliminating them, just cut the plunger off and reinstall, disconnecting the wiring. When deenergized, the plunger goes up in the carb to shut off fuel. Could the plug you used be in too far and shutting off the fuel? If not already equipped, a manual fuel shut off is a very good idea.

Good luck,


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## zhaarnak (Jul 26, 2021)

Well everyone, it does look like an overvoltage issue. I picked up a "Kill A Watt" meter, unplugged the VFO module (it does appear that this module is a safety shutdown device), cranked her up and checked volts and hertz. She is running at 59-60 cycles BUT she is also putting out *160 watts*.  This in either a no-load OR loaded (small heater) condition. So, I have pretty much concluded that the voltage regulator has thrown in the towel. What is your opinion? I am kind of surprised though. I would have thought that a solid state AVR failure would be a _total _failure, not a "partial". Is this a common issue with AVR's? and have any of you run into this issue, especially with Champion generators? As always, I both thank you, and value your responses. Patrick


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## iowagold (Jan 22, 2020)

zhaarnak said:


> Well everyone, it does look like an overvoltage issue. I picked up a "Kill A Watt" meter, unplugged the VFO module (it does appear that this module is a safety shutdown device), cranked her up and checked volts and hertz. She is running at 59-60 cycles BUT she is also putting out *160 watts*.  This in either a no-load OR loaded (small heater) condition. So, I have pretty much concluded that the voltage regulator has thrown in the towel. What is your opinion? I am kind of surprised though. I would have thought that a solid state AVR failure would be a _total _failure, not a "partial". Is this a common issue with AVR's? and have any of you run into this issue, especially with Champion generators? As always, I both thank you, and value your responses. Patrick


160 watts or volts. make a edit if it is supposed to be volts


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## zhaarnak (Jul 26, 2021)

Oops, Volts. I had a brain [email protected]


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## iowagold (Jan 22, 2020)

zhaarnak said:


> Oops, Volts. I had a brain [email protected]


lol it happens!

yea over excitation on the avr...
replace the module after you check the rotor, brushes, and stator ohms.


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## zhaarnak (Jul 26, 2021)

iowagold
That is what I am thinking. The only specification that I have been able to locate from Champion concerning rotor and stator resistance is on the stator. according to their information, the stator is good. There is no specs on stator or exciter winding ohms that I have been able to find. Dang it!


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## iowagold (Jan 22, 2020)

pm me i may have the numbers


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## zhaarnak (Jul 26, 2021)

PM sent. Thank you! If I cant find the values I will just check to see if the 2 stator windings have the same value and are not shorted to the exciter winding and throw the dice and replace the AVR.


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## zhaarnak (Jul 26, 2021)

Has anyone here come across the following article? *Genuine Briggs & Stratton Generator Rotor/stator Resistance Tables 87971GS*


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