Generac generator needs help...

[Desert_Captain]

Our Nexus Class C came with the QP40 Generac 4,000 watt generator. I had it serviced once about 2.5 years ago and it has been fine until our last trip. It fires right up but put any significant load on it like the microwave, water heater or AC and the voltage falls to nothing and it stumbles and sputters.

Had similar issues the last time and the tech found fine sand-like material in the bottom of the carb. He cleaned the carb, blew it out with compressed air and changed the inline fuel filter and we have been good to go. I suspect it is much the same problem again.

We were caught in a very nasty sandstorm last October on our way to Borrego Springs and sand got into places God never intended. I replaced the air filter on the V10 and cleaned out the battery and generator compartments as best I could and before our last trip in January. Also changed the oil, filter and air filter on the genny.

Does anyone have any other theories, cures etc.?

We don't need to use it much {81 hours in 6 years} as our two Group 27's provide more than enough power for 3 or 4 days at a time and a couple of hours of driving tops them back up nicely .Considering it has only been in for service once in 6 years though I do change the oil and filters ever year, guess it's due. Have an appointment for Wednesday morning with the folks at Simonsen Generators {an authorized Generac dealer/Service center here in Tucson}.

Like they say on TV...Film at eleven!

:h

[JAXFL]

Good to hear all is towed.

[Desert_Captain]

Just returned from Simonsen Generators... The comment about sand getting everywhere was confirmed. After the sandstorm incident, I changed the genny's air filter but, neglected to consider that spare filter had been sitting in the adjacent storage bay and had evidently taken on a fair amount of fine sand that I failed to notice.

When we ran the genny for an hour or so on the last trip there was still a lot of sand in the generator compartment that I had missed or was unable to thoroughly remove. After an hour or so we started experiencing the stutter problem under load.

Evidently, enough sand migrated into the {newly changed but less than pristine} filter combined with a slight misalignment of the filter {my bad} when I changed it was causing the genny to be starved for air. The tech blew out/vacuumed the generator compartment and installed a new filter, properly aligning it and" Voila", the genny runs stronger than ever.

He let it run for 30 minutes with the AC cranked up and she just purred. I was on the hook for one hour of labor at a very reasonable $90 and $9.45 for a new filter. Problem solved and out the door for $99.45... {Can I get a Hallelujah, or at least maybe an Amen?}

Lessons learned:

Store spare filters in a sealed zip lock baggy.
Never underestimate the power of sand to get everywhere.
Continue to carry spares.

:B

[JAXFL]

Let us know the final results

[gbopp]

Desert Captain wrote:
Not sure how sand or other contaminants could get into/through my {55 gallon Chassis} fuel tank and to the genny

It's like going to the beach. Sand gets into EVERYTHING. 🙂

Keep us updated on the problem when you get the generator running.

[Desert_Captain]

As noted I did change the air filter of the genny {along with the oil and oil filter}. I did not change the fuel filter for the genny, I have a spare but could not get access to change it. Not sure how sand or other contaminants could get into/through my {55 gallon Chassis} fuel tank and to the genny but after several years on the last filter I suspect it is time for a change.

I appreciate all of the input and will find out on Wednesday what the problem {and hopefully the solution} is. Not losing sleep over this one, just another one of the joys/ challenges of having a motorhome.

As my dad used to tell me... "Any problem that can be solved by money is NOT a problem... IF you have the money."

:B

[JAXFL]

Mine did the same thing.... Exactly... Same generator... 18 months after service... Did it again... Changed out everything and it worked.

[Turtle_n_Peeps]

My question is how did the sand get in the carb bowl? Does it have a fuel filter on it? If so, what micron?

[Chuck_thehammer]

anytime an engine has Sand anywhere.. like a sand storm.

air filter
oil and filter
fuel system flush and new filter. and pull carb bowl..

crankcase filter. (if there is one)

[wa8yxm]

Another filter to check is the AIR filter.. Like the fuel filter it can cause performance to go.. POOF.

[gbopp]

Did you change the generator fuel filter?