eu20i surging

PS I'm assuming you have fresh fuel in it too.

Classic sign of a blocked needle (hence leaning out) in the carby from leaving fuel in it. Our Honda outboard did the same thing. Not saying your problem is found, but the symptoms are similar.

Not of complete relevance, but do you have a Service Manual?

I know it won't fix the issue, but always handy to have.

Let me know if you'd like one.

Cheers.

Had the same problem with my 1k Honda. Bad fuel. Had to pull the carby apart and clean it out. No problems after that.

Capt.

Swampy is spot on with his advice. "Carburettor & Throttle Body Cleaner" in a spray can from any automotive spares shop is magic stuff to clean out carburettors and injectors.
Tiny orifices in carburettors regularly get blocked by gum, varnish and dust - that combined, make a nasty mix.
I spent a couple of days trying to find the source of a carburettor blockage in a Briggs & Stratton lawnmower engine, belonging to my old Italian neighbour Barney.
It wasn't until I found a cunningly-hidden carburettor orifice that was completely blocked, and which I cleaned out with a dose of C&TBC, that the Briggs started to purr like a new one again.

Cheers, Ron.

What makes you think a Honda mechanic is better or more qualified than any other person who knows about how a carburettor works?

Yes it is a problem with electronically controlled gensets and gear that is electronically controlled running off them. Some soft start bore pumps and transfer pumps have the same problem running off gensets and a special card has to be used for the pump to work.

For the OP. One thing about the problem is. The honda manual states, the fuel should be drained if the genset is not in use. I never have a problem, as I drain mine until I need it again.

https://www.youtube.com/watch?v=njNMxlNseRg

Link didn't embed sorry.

hi
My local stihl/ Briggs agent does not warrant if customer has been using it .[Briggs thinks it is the cause of melted pistons etc ] Ya kidding !! [nothing to do with these engines running leaner as they get older .]Did I mention that briggs exhaust valve heads fall off but of course this is the fuel you used !!!!!!!!!!
This is complete opposite to what fuel companies mention . As we all no the higher octane recipe resists detonation more effectively in an engine that needs it .
Typically an engine that has more static and dynamic compression .Both of these are influence by many factors cam timing ,ignition timing and etc etc
The higher octane fuel also contains a very high level of cleaning agent .

swampy

not particularly exited about Briggs any time ..... serioulsy don't get me started.

But I have experiences Sthil and Honda motors being hard to start and failing to idle when run on high octane fuels.

cheers

hi Bantam
Every one has a story but agree on the Briggs .
The vanguard series is the best and only to consider which is ok [engine block is MItsubishi with chinese small parts ] but there top rings exhaust valve carburetors are rubbish.
Honda stationary motors are ok but nothing spectacular . They can still have some issues .
There generators are ok but not worth the dollars if there asking around 1200-1300$ maybe
Stihl products are above average except much of there hand held equipment destroys/burns out ignition coils regularly. There early 4 stroke hand held stuff had many problems also . There later hand held gear is great .
All of these brands luv to be >>>fully>>>> serviced regularly clean new fuel top of the list .
This includes valve adjustment ,fuel tank clean ,decarbon clean out as required , governor check /adjust etc etc ,calibrate high and low speeds etc etc . In my exp. they respond well to lots of TLC. A little high maintenance /touchy in my opinion

Once they all start to loose a little compression and get a bit of wear this makes them become tempremental after about 2 yrs of good work use

I use high octane fuel in all my home based stuff and it runs well . Mainly to take advantage of the cleaners in the fuel . Most pieces i have donot start the first time. The stihl chainsaw is a f...ker since new .

That reminds me I have to run up all my gear .
Small engine varies a great deal between people its amazing.

swampy

I don't understand this as I have a stihl whipper snipper, Honda genset and briggs and stratton powered mower all running on 95 ron. All of these have never given any problems with the exception of the briggs and stratton, that I replaced the output oil seal on.

Mower engine 12 years old and the previous one 24 years old before the mower fell apart.
Honda EU20I 8 years old.
Stihl tow cutter 6 years old.

I don't see any mention off maximum fuel octane rating in the manuals but I do see a bit about ethanol. In fact a lot about it.
There can be a fuel mix adjustment on some small engines due to the octane rating but also remember the yanks have a different calculation for their octane rating

All that seems to keep them running well is. Clean fuel, clean air and draining the fuel in both the Honda. I don't even throw the 95 ron out during winter as I hit it with fuel stabiliser. With the fuel stabiliser in the 95 ron 2 stroke mix for the tow cutter, I leave that in over winter and it starts first go, the same as the Honda and the mower.

hi Bantam
As I luv fooling around with small engines was it B&S vanguard series engine u were having trouble with or one of there intek or smaller versions ??
The vanny I call them is what I no the most about, but the inteks and others are only a cheap copy of the vanguard series . In saying that the Vanguards are not perfect either .
Interested

I do smallish engines because building real motors is so dam expensive ha ha

swampy

hi to all
If your hand held gear or otherwise is fitted with carburetor mixture limit caps remove to tune when both hot and cold then reinstall them . [The limit caps only give 3/4 turn available].
Be careful as u can damage the cap and or the needle. Reinstalling the caps can stop the needles coming out of adjustment and prevents the needle from completely falling out.

swampy

I should have added that I always drain the Honda as per manufacturers manual when not in use.

Ditto what Slow One said above about RON 95.

Only difference in the Honda Slf Propelled is now 21 yesrs old,
The EU10i 15 years when I sold it & still running fine.
68cc Husky saw is 23.
36cc trimmer is 26.

All have spent their lives run on 95 Octane.
2 Strokes on 50:1 with synthetic oil.

Spark plug replacements on all my equipment has been few & far between.
Won't say the same for engine oil, I've always considered it cheap maintenance.

Cheers

I am pretty sure that the only reason single strand game fishing trace wire was invented was for cleaning out Honda jets haha. Glad to see you had success.