that's what it sounds like to me too... motor is running fine off the idle circuit. which will support low amp loads. the second you put a large load on genset. motor control opens up throttle, then dies.
high probability your main jet is clogged, which almost always happens when you let any small engine sit any amount of time. the proper way to put up any small engine is to shut fuel off, then let motor idle until it dies. this uses up all the fuel inside float bowl. nothing inside fuel bowl to dry out and gum up your carb.
other possibilities that could go wrong is electronics ... all sort of problems are possible. everything from losing magnetism, bad brushes, bad diodes, mouse chewed wiring, etc, etc.
rebuild your carb... betcha your genset will run nicely again.
high probability your main jet is clogged, which almost always happens when you let any small engine sit any amount of time. the proper way to put up any small engine is to shut fuel off, then let motor idle until it dies. this uses up all the fuel inside float bowl. nothing inside fuel bowl to dry out and gum up your carb.
other possibilities that could go wrong is electronics ... all sort of problems are possible. everything from losing magnetism, bad brushes, bad diodes, mouse chewed wiring, etc, etc.
rebuild your carb... betcha your genset will run nicely again.
I'm late to the party, but it doesn't sound like a demagnitized coil...since it's producing power but quitting under load.
Possibly a carb issue. How long has it sat with fuel in it? Could be gummed up, could need some tuning. Air filter dirty? Might be time for a cleaning.
(when you were running the blower, were you running the electric heating element too?)