Thor Forums

[FW28z]

You should not only run it once a month for 20~30 minutes, but you should run it under load.

An under load means at least 50% load.

Like most RV'ers, my My Onan 4000 does not get run a lot. I did run it for 20 minutes a month in the winter, but the first time I used it this summer, it had trouble running under a 50% load. It ran OK with a small load (fridge and battery charger), but it would "speed cycle" under a 50% load and not produce a stable output.

I ended up having to spray carb cleaner into the genny several times (turn genny off, spray carb cleaner into carg, restart genny... repeat several times).

After doing that, the generator ran just fine under a 50% load.

Before I retired, we had emergency generators at work that were critical. We actually had to run the generators once a week for 1/2 hour under full load of the facility.

While it seems perhaps a bit extreme, we had to do that to satisfy a UL requirement for our facility.

So for my RV generator, weekly is a bit extreme, so I do it monthly under 50% load, especially since I know better not to as I did last winter.

I have a ceramic heater that provides the 50% load that simply plugs into an outlet. My advice then is not only to run your genny monthly, but run it under load.

And Stabil is a good idea as well. However, with most RVs, you have to pour it into the RV's main tank, which is not a bad idea as it protects the motorhome's engine as well.