Sounds like a couple of things are going on. I think the power factor is an issue, and your generator is probably starving for fuel.
Power Factor: the ratio of the actual electrical power dissipated by an AC circuit to the product of the r.m.s. values of current and voltage. The difference between the two is caused by reactance in the circuit and represents power that does no useful work.In an ideal world, the power going into a charger would equate to the power coming out. In the pics below, I have an Iota 75A 12V charger connected to my solar battery bank. Power = Voltage x Current.
75A x 12V = 900 Watts. On the supply side, power should be close to the same 900W/120VAC = 7.5A.
But here are my actual readings:
The charger is supplying almost the full rated 75A, but instead of drawing 7.5 Amps from the generator, it's drawing 13.56 Amps!
13.56A x 120VAC = 1627.2 Watts being supplied by the generator!
A lot of wasted energy from a poor Power Factor.
These chargers usually have a high start up current/charge rate, but tapers off quickly unless the batteries are very dead. That may be enough to stall or trip the overload circuit on a generator. I have a Yamaha EF2400iS, and while it grunted a little, it had enough power to continue charging.
ALL of these small generators (Honda, Yamaha, etc.) that have variable speed engines, have very small jets in them. There's no fine fuel filter inline. Any speck of grit in the fuel can cause issues. If the fuel demand exceeds the available fuel flow, the motor will stall.
Here's how I cleaned my carburetor and added a fuel filter:
http://2manytoyz.com/carbfix.htmlFWIW, I tried Seafoam. That works on a carburetor that has stale fuel that has become sticky/gummy, but doesn't help with a piece of grit in a jet. These carbs are not difficult to work on. Amazing how well the generators work after a proper cleaning.
