Yamaha EF1000iS Generator

[Skywatcher]

Greetings All

I don't know if anyone remembers me posting about a Yamaha EF1000iS inverter generator running out of control on the old PERR forum. Well, it's been sitting in the back of my shed for the last several years and I thought I'd take another crack at it. I had been working on another Yamaha inverter generator, about a 2,500 watt unit, had to replace the main crankcase gasket and when I put it back together, it too ran out of control because I had forgotten to reconnect one of the harnesses to the mother board. Reconnected the harness, and the machine ran perfectly. Anyhow, this is what inspired me to take another look at the little Yamaha 1000. No loose wires, no broken or shorted wires, so I figured it was time to start grasping at straws.

I actually grasped the right straw this time. Knowing that I was not the first person to have the carburetor off this unit, I thought I'd try something out in left field. I removed the throttle shaft stepper motor, turned the armature shaft 180º and reinstalled it. Bingo! the throttle control worked perfectly. Now the little unit hits its stride and doesn't miss a beat no matter what load it's under (within rated load). Figured I'd share this with the forum family just in case someone runs into the same issue with an inverter generator that someone else has had apart before it's brought to you. All the very best,

Sky

[KE4AVB]

Sounds like it was opening instead closing the throttle vane then.

As far working any equipment here other than my own I do assume someone else has been wrenching it. I know for sure over half what I work on that others has been in there before; some are more obvious than others. It one of the reasons it takes so much extra time to get to real problems.