looking for carb for Shop Force AT 04103 generator

I checked the governor springs as per the link you posted and all looks good. I will attempt to reset the governor next. If that does not correct the problem I will create a support ticket on the Generator Gurus site. Thanks!
 
You need a tachometer to properly set governed top speed. Need to check at both load and no load conditions. Can’t just go by spring location. I should add that if you find that the RPMs are off and you adjust the carb to specs, you should also check the voltage and hertz output. If these are out of specs you could easily burn out equipment or tools.
 
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I would use the choke, or something to substitute and richen the mixture with the choke to see if that stopped the surging. That will tell you if it is running too lean. You can cut the fuel off and let it die from starvation to see if it is too rich. If the rpm gets better when the mixture changes then you will know it is a mixture issue. If the mixture does not improve then you will know that it is not the carb. Sometimes the placement of the spring can make it more or less sensitive to surges. Also you can hold the throttle steady by hand and see if it runs steady. That will also tell you if the carb is metering fuel properly, and the governor is at fault. I've seen engines run lean also because the fuel flow into the carb is poor due to the filter or filter sock being plugged.
 
Change the governor spring at the arm by one hole at a time. (Pen mark the original hole so you don't lose track of where you started). Don't mess with the governor shaft lock cross bolt. That is a mistake a lot of people make. The governor only has one job and that is to keep the engine from trying to run out of control at high RPM, that is why it has a tension spring. The governor only responds to what the carburetor is doing with the fuel/air mixture. The carburetor literally operates the governor, not the other way around.

These carburetors can be a little moody to deal with.

Top RPM should be 3600 RPM when a load is applied to the generator. The output can be measured with a simple device called a Kill O Watt". Generators do not have a low base idle setting like a mower engine does. You should have a Hertz reading of 60 and about 120 Volts.

James Condon on You Tube has a lot of good videos about these cloned Honda style engines and the carburetors. Even the replacement carburetors often need a minor resizing with a pin drill of the pilot jet from time to time to get them to run correctly.
 
Well, too late: a few days ago it finally got warm enough for me to work in the garage without me freezing too much. I did mess with the governor shaft lock cross bolt (as per the adjustment procedure specified in the Generator Guru troubleshooting flowchart). I also replaced the small spring which encircles the governor rod (it had popped off a few times and looked a bit wonky). After doing this adjustment/replacement the surging was gone. I can see the (rough) measurement of 120 volts on the analog meter of the generator. I need to now measure the frequency (I may have a meter that can do that, otherwise I may invest in a Kill-a-Watt). I was able to power a couple of heaters without a problem but have not done any more quantitative tests on capacity of this 2500 Watt generator.

Interestingly, the clone carb I installed leaks fuel. When I opened it up I saw no problem with the float/needle. I applied a bit of pressure with my mity-vac and manually moving the float up creates an air seal. So nothing obvious. I ended up putting the original carb back on (which has an idle fuel screw that cannot be adjusted because the end has broken off) and the fuel leak is gone and the generator runs fine without surging.

I have been watching James Condon's videos on generators/etc. Agree that this is a wonderful source of learning.
 
You will need a meter which measures frequency in hertz. Two things you need to know that depending on the size of the generator the hertz will vary. If your generator has an output of 110 VAC the frequency will be 50 hz. If the output is 120 VAC the frequency will be 60 hz. Your hertz may vary + or - 1 hertz
 
You guys do know how to use a RPM meter to set Hertz of either a two pole which most Gas powered generators are, or a Diesel 4 poles right?`

Off load you are looking at 62.5hz USA or 52 hz otherwise. The output voltage is dependent on how the generator is regulated. There are those with capacitor regulators and those with ACR regulators. And some with the ACR are actually adjustable. And my info is right this generator uses an ACR so trying find the HZ using the voltage may not even work as its is regulated.

Rivets based on stated voltages why is my 130 vac still 60 hz from the local Utilities?
 
I do have a meter to measure the AC frequency but I do not know how to modify the frequency of the generator. Other than a few different holes for the governor shaft spring, I see no governor adjustments (unlike some videos I watch where there is a screw to fine tune the tension on the spring). The carb that is currently installed has no external adjustments (idle fuel screw is no longer moveable). How would I go about adjusting the frequency?
 
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