Generac 3400watt won't idle with no load, Help please.

thanks for all the suggestions so far.

It would not surprize me if it was someting as simple as the airfilter. The rig did sit for almost 2 years before getting sold. it could be very possible that the filter got fouled while sitting.

I am certain this is a minor issue. the unit ran flawlessly before this.

The inverter, (or more accurately,...the Power Converter unit) has been upgraded from the original Magnetek (sp?), to a nice 4 stage WFCO unit purchased from Randy at BestConverter.com.

It has been a great unit/upgrade with no issues what-so-ever since installed.

Thanks again for all the help, and please keep any more suggestions or advice coming.

On edit- OOPS,... I forgot to add that I was always mindful of the loads between the AC and Microwave. I have never ran them together at the same time.

Cheers,
Ron

I was the sad previous owner of a Generac 3400....you can download the service manual (use to anyway I haven't checked lately)..this gen set does things totally different from Onan...

Make sure your air filter is clean...if it is it is very doubtful the carb or engine is the problem.

it is a very complicated system....your gen. has a very sensitive control system.

and other than the r.v. dealer in Las Vegas knows how to trouble shoot the system I don't know who does...check with Sleepy he had his worked on in Las Vegas...

but just the basics....your Generator puts out approx. 650 volts.d.c. that feeds an inverter somewhere "inside" your camper...that is what controls the output to 110 volts. a.c. 60 cycles.
anything that it senses as a problem will shut your system down.

"If" that inside inverter gets too hot (and mine did) it will shut down...I had to remove the false bottom of a drawer to allow enough ventilation and no more shutdowns in hot weather.
You will get no support from Generac...pick your service man carefully...you will wind up worse than before...when it works it is great..but to make a compact unit that will work with the a.c. and the microwave on you need the 3400 watt unit..
Lance finally threw up their hands and went to Onan 2800 ..you just can't always use micro and a.c. at the same time...
but back in 2003 no one would touch Generac because they would not pay warranty..plus there is a big learning curve on that unit....
I had a loose wire that I found when I realized I would never get any warranty on the unit. but it would not even start...your engine is changing engine speed ( I am thinking) is trying to maintain 60 cycles..if it tries a few times to maintain 60 cycles and can't it will shut engine down..

One thing ..back then Lance made every effort to help me but had no luck with Generac.
that being said....good luck....

Surging like that indicates a carbration issue (out of adjustment/dirty) Specifically too rich as I recall from my small engine mechanic days (But those were a long, long, time ago)

Not much more I can add.

It does sound like a carb problem. Typically propane generators do not have the normal sticky gue in the carb, but in your case - probably lack of use is the problem?

My guess is to have the new owner run the generator with a electric heater as a load (less likely to get messed up by a wrong voltage or frequency, and very cheap to replace if it does). The 1,500 watt load will put some load on the generator without overloading it. The hour or so of run time should put some fuel through the generator carb, and clean it out.

If it is still messed up, then a pro needs to look at rebuild or replace the carb, if that is what they feel is wrong with it. Anyway it will work under load, so it is not your problem. .

Fred.

never mind