Exercise Gen. with load when cold outside

Running it under load is good practice to ensure everything fully warms up, but I still question the necessity of running it at all. Cold starts is one of the hardest things on engine bearings. I have let the engines in generators, RV's, classic cars, backhoes and boats sit every winter (6 months or more) and have never had an issue in over 40 years. Maybe I'm just real lucky, but I doubt it.

Lou
05 Travel Supreme Envoy

mpierce wrote:
Well, that is what a lot of the mfg's suggest. The load is to get both the engine and the generator warm enough to drive any moisture out.

Actually just running the engine long enough to get hot will drive out any moisture, load or not.
In my opinion I believe the load test exercise is to check whether or not the "governor system" is working to provide stable power under load. In other words, does the engine automatically supply enough throttle to maintain 120 volts and 60 cycles as the load changes?
The thing is, unless you also set up a meter to measure the exact voltage and frequency, all you are really doing is just running the generator and seeing if it powers anything. You have no idea if the frequency is correct or the voltage is stable.
Commercial buildings that have generators do not run their generators under load but they do verify that the engines start and produce power.

Well, that is what a lot of the mfg's suggest. The load is to get both the engine and the generator warm enough to drive any moisture out.

I'm not sure where the practice of running a generator with a load got started, but my 8.5kw Generac at home starts once a week and runs for 10 minutes with no load. Once a year, the service guy changes the oil and runs it under load. It sits outside in the elements just like the Onan in the Sahara.

It's a good idea to make sure your genny is providing power, but running it at 80% for an hour seems a little excessive.

4aSong wrote:

gbopp wrote:
I use a 1500 watt electric heater. Or two, depending on the size of your generator.

This is what we do.

X2

352 wrote:
Turn on the kegerator.

Why would you ever turn it off? :)

When I start my Onan generator, all parts of it are being exercised, including the engine and generator portion. Once I verify that it is capable of producing electricity, I do not bother to keep a big load on it, but that's me. It's worked for decades with all of my generators.
Commercial back-up generators at hospitals and other commercial buildings that I have built only verify that the engine is running and electric is being produced. They do not shut down the power in those buildings to exercise them.

Turn on any and all electric appliances...heaters, toaster, coffee pot, heat pump, refer, stove if electric, AC fans, electric frying pans and griddles, dryer, floor heat...and any thing else.

Best to install a fuel petcock valve between the supply and carb. When done using the genny shut off the fuel petcock and walk away. No need to exercise there after.

I know opinions vary, even among specialists.
I've got a 2800 watt Onan. I use two space heaters, one on high (1500 watts) one on low (750 watts). That gives me about an 80% load. Do that for 1/2 hour once a month. I figure that should replace the fuel in the carburetor, get the windings warmed up and should have enough current in the slip rings to help clean them.