Yamaha ef1000is was rained on, starts and runs after unplugging wire plug from generator, runs when replugged, but no electrical output

The OHV engine requires periodic valve adjustment.

Make sure there are no vacuum leaks on the engine manifold side of carburetor. There are 3 o 4 pieces on the engine side so inspect well.

If no leaks on engine manifold side then likely there's a blockage somewhere in the carburetor high speed circuit. Most economical solution is chinese knock-off for ~$20 US delivered.

If you can't find a cheap replacement then you'll need to do a deeper clean of carburetor by removing welch plugs and submerge in carb cleaner. You will need new welch plugs (kit) and likely kit will cost more than a knock-off carb.

Before tearing down carb, you could try Seafoam fuel treatment... probably less the 50:50 chance it will clear.

the circuit breaker has not trip and its generating power

it seems to be the standard that the rating or model ??1000 or ??1500 or ??2500 or ??5000 or??5500 or ??6500 is the kv rating of the gen-set regardless of straight or inverter
so if yours is EF1000 it will be 1000 watts or 1 kv
remember that most electric drills are 1000 watt units so a unit this small is mostly good for lights, charging batteries, small compressors for tyres

Try searching for a fuel shutoff somewhere near the bottom fuel line exit for the fuel tank on somewhere on the fuel line.

bad gas.

It is starved for fuel. PROBABLY needs to have carbureator cleaned and adjusted OR the fuel filter may be clogged.

Tom...what can I say - what you did was not very smart. Next time draw a diagram BEFORE you take the wires off!

Try the filter in the gas tank.