Hi guys, my EU2000i surges real bad when I flip the switch to Eco-Throttle mode. It runs fine at full throttle. The genny is just over a year old, with maybe 20 or 30 hours on it. I always drain the carb bowl too if it's going to sit for a while.
So last night I pulled the carb off and blasted it out with Gumout and air, put it back together, and same condition still. The oil is full, so I don't think it's the low oil shutoff trying to kill it, and the gas is fresh.
I've heard that the vented gas cap could be the culprit, so before I take it in for service I'm going to run it with the gas cap off, and if that doesn't do anything, I'm going to turn the only screw out a little on the side of the carb(air or fuel, not sure).
Any suggestions??
Thanks !

 

Hmmm...You've pretty much covered everything.
These units are pretty suseptible to stale fuel- I use Stabil instead of draining.
On mine, it would pretty much stop running altogether if I forgot to open the fuel cap vent.
That adjusting screw is an air bleed to smooth out engine acceleration off idle or eco mode- that may be the culprit.

In any case, let us all know what you find...

 

Plug a small appliance in while in the econ mode. Check for surging.

Honda's sometimes had a vaccuum passage through the gaskets for their throttle control on the carb that may be plugged with goop check them thoroughly for correct placement or foreign matter.

Rick

 

Rick, the carb and gasket are both spotless...good suggestion though.
Well I tried running it without the gas cap during lunch, and it still does the same thing. The only screw on the carb seems to be just a throttle stop screw....I backed it out all the way...no change....turn it in all the way, and it puches the trottle up to a higher rpm.
The one thing that did smooth out the EcoThrottle RPM was moving the choke to about half
Still confused...I push the choke and it runs good. Is there another mixture screw or something I should mess with?

 

It's still under warranty. Honda will take care of you guaranteed. Good luck.

 

I'm thinking that when in the econ mode it surges when idle to conserve fuel by design. Did you plug something in to test?

Rick

 

Yes, I plugged in a radio and a desk light (25W bulb)....still surges. It didn't surge when it was new.
I dropped off the carb at the local Honda dealer this afternoon. They're going to clean it in an agitating/vibrating carb bath, and test it on another genny.
It seems that the idle circuit holes/passages are VERY tiny and are susceptable to blockage. They said they've had luck cleaning them this way in the past. I'll get it back Friday and post results.

 

Moose,

I'm a Honda certified small engine mechanic amongst other things keep that in mind for future reference See my first post

Those passages are almost invisible to the untrained eye and easily clearable with some spray carb cleaner. Believe me when I say they have had me stumped before.

Rick

 

Rick, I appreciate your input on this, especially since you're trained on Honda's. When I pulled the carb off yesterday to spray it, that was the first time I took anything apart on it "under the hood" except for changing the oil.
I guess i could have soaked it in some solvent, pulled the main jet and anything else out of it, and used air to blow it out myself Hopefully they can get it clean enough to run smoothly again.

 

It has to be asked.

Have you checked the lift pump?? Maybe try a Walboro?

 

I put a FASS on it already....it nearly doubled the weight of the unit.

 

Mine will surge with ecothrottle on when the engine is cold, so I let it warm up a few minutes before letting it throttle down.

If it hasn't been run in a while, might try fresh gas with some intake cleaner in it, and burn a tank through it with a load on it.

 

ok, it's all better now. I took the carb in and they soaked it overnight, then hit it with air. I start it up in regular mode, run it for a couple minutes, then switch to Eco....nice & smooth.
Their tech told me to always open the float bowl drain screw and drian the bowl if it's going to be sitting for more than a couple days....which I will do now, and to run premium in it. I actually got 11 hours of run time this past Tuesday night in Eco mode at 6300' elevation off a full tank (1.1gal)
Next time if it happens again, instead of paying the $10 I'll soak it and blow it out myself.