Outdoor Power Equipment (Lawn Mowers, Snow Blowers, Chain Saws and more) Discussions

Hi guys. I have tried getting to the root of this problem via other forums without luck.  After doing some searching, I was able to track down this forum, it's great!  I have a problem with my Honda EX350 generator. Here's some information regarding this unit in case you haven't seen one before. It is powered by a small two stroke engine mixed at a 100:1 ratio. The carburetor is mounted to the bottom of the crankcase and uses a single metal reed valve. The igniton is a solid state design. Because the generator is of an inverter design (much like the newer Honda generators), the engine does not have to run at 3600 rpm. There is a low rpm position (150 watts) and a high rpm position (300 watts). Here is the problem.

When in the high rpm position under full load (300 watts), after almost exactly 2 minutes of running, the thing bogs down for about 6-7 seconds (just like you were putting the choke on), then goes back up to normal rpm. This goes on until it runs out of gas, like clockwork, every two minutes. I cannot figure out what is causing this. I have checked absolutely everything and have come up with nothing. I have a friend who owns the same unit, and after spending hours troubleshooting my generator and finding nothing, I was forced to simply change parts to see if I could find the problem. Here is what was changed.

air filter, carburetor, reed valve, spark plug, exhaust, gas cap (vented)

None of this fixed the problem. The thing is, the engine starts first pull every time and runs at a steady rpm.  The engine just seems to be loading up and just bogs down for a few seconds, then it seems to clear itself up.

Here's the thing, partially blocking the air intake with my thumb causes the engine to run the exact same way until I remove my thumb. But when the engine experiences the problem by itself, it only happens every two minutes.

Does anyone have any ideas what might be the problem, I am out of ideas.

your lil engine is running lean...

needs a crankseal or possible cylinder gasket.

no big problem.

later chris

Chris, thanks for the suggestion.  Could you please elaborate?  Thanks.

you mentioned that you tried a few other fixes and nothing really worked.

when you partly close the choke it smoothes out a bit.

this leads us to beleive that there is a lean condition...not enough fuel in getting in the engine.

so either there is a fuel delevery problem ...you switched out carbs and checked that end,so its ok there.

or the extra air is coming from somewhere else...usually a crankseal.

on your genset ,i beleive that one side of your crankshaft goes into the gen side and the other side is where the start handle is.

i would check the easy side first.

later chris

Chris.
Can you find a vacuum leak on a two stroke like you would on a four stroke? Like spray some WD where you think the leak is while it is misbehaving and see if it makes a difference?

Hey Rob ...thats an excellent way to find the leak...

i usually use a little THICKER spray.wd40 dosent really have enough oil in it to stay around long.

i sometimes use a product called MOOVEIT,not sure if its available in your area.

any fluid that will burn in the crankcase should work pretty good.

you just spray it on and the engine will act a lot different when you find the seal or gasket problem

later chris

So Bill, was this mystery of yours finally solved?

I have also got the same problem, my friend gave me it and every were said it was 100:1 fuel mix when that is not correct it is 50:1 if you read on the filler cap and on the body of the geni, when i was told it was 100:1 i thought that aint alot of oil this could be why the machine is surging, my fist guess is the crank seal leaking air as it isnt being lubricated anuf

did you eva sort your problem out if you did what did you find?

Danno

Hi,

I am from the UK and have the  almost the same fault

I run the generator and when I first start it, green light is on then goes onto red overload and pulls the revs down

if you take the inverter cover off you might feel it hot in one place and you can also disconnect the blue socket

and just run it on 12v to try it you should see a diffrence.

I am sure you have nothing wrong with the engine but its worth checking the

float valve it could be trying to flood the carb but manages to keep going when its cleared.

if you happen to find any iverters for mine please let me know.

Les

Hi spacom.

Did you solve the problem with your EX350 ?

I recently ran across an ad on Craigslist for a used, inoperable EX350 for $100, so I bought it thinking that I could get it going relatively easily and at a reasonable cost.

Are there any special starting procedures for this machine??

The fellow I got it from said that he used it 2.5 years ago, placed it back in his shed where he stored it, ran across it last week when cleaning the shed and decided to sell, which is where I enter the picture.

The tank was empty, so I promptly filled with petrol with a 50:1 mixture. Attempted to start and nothing.

Removed the plug, and it appears to be brand new.

Checked for a spark, and there is none. Knowing that it is relatively rare for a coil pack just to "go out' from idly sitting in a shed, I am curious to know if I am missing something other than my mind.

Any and all help in this area would be tremendously and greatly appreciated.

Yours,
Jon