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

is it better to run the generator once a month or can it be stored until it is needed.I read it should be run monthly under load so the generator head stays magnetized.Is this true?

I have a Coleman/Powermate generator I bought in 1985, I always store it dry (tank and carb.), never had a problem.  This past October with the blizzard and 3 1/2 days with no power it fired right up and got me through. The last time I had used it probably was 7 to 8 years ago, stored dry , covered in my garage. I did switch over to a synthetic oil half way through the last power outage. Since my last usage I have read alot about having to "excite" some units, I guess I must have been lucky during all these years. 

the key to not losing the magnetizem is to disconnect the load on the generator before shutting it down.   Shutting it down with a load connected is a no no

carlb wrote:
That makes sense not just for the generator but also whatever might be on at the time of shutdown, such as electronics etc. 

I have a 60 amp main breaker that I always throw before shutting down the power plant.  In all of my years, I've yet to have a problem.

yes electronics and even electric motors wont like it when the engine spools down and the voltage and frequency starts to drop

  Quite often during my long term outages my generator just runs out of gas......I just go out and fill-er-up again, starts right up and generates. Could running out of gas cause a problem? Sounds like I may be luckier than I think.......

That is, after it runs out of gas I disconnect it first, fill-er-up, start it up, then reconnect to my system. This is a wonderful site...... 

letting it run out of gas under a load is not good for the gen head or the loads that it is powering.   If you are running out of gas I suggest you go out to the generator when you have at least 1/2hour left of run time, disconnect the loads and shut it down to re-fill.  Some might refill it with the engine running but you are taking a big chance if you spill gas on the muffler or exhaust.  

The other option is installing a larger fuel tank.

Roger the good suggestions carib, I will do a better job of filling before running out. All this good info/input is well advised. Just never knew or heard that a shut down because of  gas shortage could be a problem. I will heed this word to the wise............thank you for the tip...... 

One explanation that I heard for why to shut down "manually" (shut off and disconnect the loads, then kill the engine), vs running out of gas, was:

- The more obvious, the voltage change and frequency change will likely not be good for electronics/motors. Maybe not a problem if you're running a simple light bulb, or basic heater ("dumb" resistive loads). But sounds like they could be rough on other devices.
- The aspect I'd never considered was that there is a voltage regulator in most modern generators. It's some sort of magic (to me, at least ) electrical device that basically amplifies the generator head's output voltage if it's below, say, 110V, or regulates it down if it's too high. Under normal operation, the regulator's job isn't too bad. But during an out-of-gas type shutdown, under a load, the generator head's output voltage drops as the engine slows. As the source voltage drops, the regulator tries to keep sending 110V to the outlet, so it cranks up its amplifier, can overheat, etc. Over time, you can damage the regulator when shutting down like this.

I have no idea how quickly real damage to the generator could happen. But I've been sure to avoid running the generator out of gas, on the occasions I've had to use it.

Plus, if you're going to shut it down "permanently" (not just filling the tank quickly), you want to disconnect the loads, then let it run for a few minutes under no load, so the engine's internal temperatures have a chance to drop, and equalize. Otherwise it's hot from running under a load, then when you abruptly shut it down, the airflow stops, and it stays quite hot, with localized hot spots. Again, just what I've read. Maybe a few minutes with no load is not really essential. But for the rare times I use it, trying to treat it "gently" is not a big deal, and is cheap insurance.

Of course, also disconnect any loads before starting it. Then connect them on one by one, once the engine is warmed up. Having a few motors (fridge, furnace, etc) all trying to start at the same time will put a really big load on the generator.

Back to the original question, I don't run mine monthly, the way the manual instructs. But I have not had a problem when starting it back up after maybe 6 months. I do plan to start shutting off the fuel flow, and running the carb dry, before storing it. Until now, I'd been shutting it down, *then* closing the fuel valve. That leaves gas in the carb, which can gum it up. For an engine that I do not run often, but is really required when I need it, I want to reduce the chances of a problem. Use fuel stabilizer if you plan to keep the gas in there for a while. Better yet, don't keep any gas in the carb or tank. As was suggested, keep it in cans, and put that gas into the car periodically, to keep fresh gas around. Sorry for the long post.

Real generators may lose their field strength over time. Self-exciting alternators do not have such problems. You may want to check you owners manual to see what you have....check to see if it refers to "flashing the field" or such. As far as cooling a generator/ alternator.. There should be no "hot spots" in the unit. Even a 240 v generator only running on one phase at full load should be able cool itself or disperse heat evenly, copper being the secound most wildly used thermal conductive metal after silver... My 2 cents Friiy