Running Gen for short amounts of time

[toytacoma8]

I have a new to me toy hauler with an Onan 4000 Microquiet, I don't have the manual and was wondering if there was anything specifcally to look out for. Also is it ok to run it for a few minutes at a time like at a rest stop or should there be a minimum amount of time?

THanks

[joebedford]

I did not like the propane generator in my last rig. It was very hard to start in really cold weather (20s) and that was my heating fuel the generator was using up really fast.

I like propane for heat and gasoline for generator. (have that at my stick house too).

[2oldman]

Handbasket wrote:
Only thing I worry about on short runs is the inside-the-box muffler. It's stainless steel, but if it does get eaten thru by the water and other stuff in the exhaust gasses, it'd be a bear to replace, and no doubt costy.

Short run times for automobile exhaust systems do not heat the pipes enough to evaporate condensation. Next time you do that, watch water drip out of the tailpipe.

[MEXICOWANDERER]

"as long as resupply is not an issue"

It's great when a bulk truck comes along, strings a hose to a 500 and then goes away. Not so great dealing with double-digit IQ personnel at a distant gas station.

[mlts22]

If I had the choice of fuels, just choosing by the fuel, I'd go with propane every time. It burns cleaner than gasoline (doesn't need fancy emissions systems), doesn't foul up the carb with varnish, and it isn't toxic to the environment should it vent (assuming no flame sources nearby, of course.)

However, propane has less energy than gasoline and in my neck of the woods (which is ironic being in oil/gas rich Texas), finding refills close to where I live is hard. Of course, there are always Extend-a-stay mechanisms and such since getting a bottle exchange at 1:00 in the morning is a lot easier than finding a filler open that late. So, for convenience factor, gasoline is hard to beat even though propane is a cleaner fuel.

Then there is diesel, but a diesel generator has to have so many more subsystems than a gas generator that the price and upkeep are a lot higher. A gasoline generator I can change the oil and air filters, perhaps blow out the spark arrestor, and be good to go.

[MEXICOWANDERER]

Another issue regarding condensation in oil is that oil dirtied by gasoline byproducts is like a hundred times as vile if it should see condensation. This is one of the few areas where LPG shines over alternative fuels.

A bunch of wealthy folks outfitted eight cabins at a Sierra Nevada lake with a ton of 2-volt cells, a pair of linked Trace 4048 inverters, and a 48 volt battery charger the size of a credenza. The power came from a Wisconsin V-4 running a 15KW generator. Every cabin had a REMOTE generator start/stop switch. A pair of 500 gallon LPG tanks for energy.

I had to do it this way because of the spurious nature of start/stop. The families had orders to run the generator rather than a microwave longer than ten minutes or Air Conditioner. In one 12 day period during the summer, the counter clocked 73 starts.

LPG has its place. Limited, but irreplaceable in its function. I do not like gasoline in sporadic used genset motors. Great for repair bills (the mechanic) but headaches for the owners.

[DiskDoctr]

toytacoma8 wrote:
Thanks for the replies, sounds like as long as I run it for 30+ minutes at some point during the month I am probably OK to run it as needed on camping trips.

One caveat I would add for short runs. The Onans will often run rough at first, then smooth out. You want to be sure it is running smoothly when you shut it down. If not, it can be more difficult to start the next time.

A downside of not running frequently enough is the gas in the line from the tank dries out and when starting it, it must crank dry until the line is again charged before it can even try to start. You can add a priming circuit to it for under $50 to avoid hard starts (beginning of season, first day of camping trip, etc)

[toytacoma8]

Thanks for the replies, sounds like as long as I run it for 30+ minutes at some point during the month I am probably OK to run it as needed on camping trips.

[Handbasket]

MEXICOWANDERER wrote:
LPG is excellent for short term use with generators as long as resupply is not an issue. Benefits include running better when cold, absolutely no oil contamination or spark plug contamination. Downsides are increased fuel consumption higher running heat generation and slightly less fuel economy. I would personally NOT run a non-LPG generator for less than a half hour.

One other downside... the temptation to skip exercise runs since there's much less danger of the carb gunking up. Condensation still forms in the oil and the exhaust still puts water in the muffler and exhaust pipe. If you're in a humid environment, there's likely to be at least some condensation in the generator section. The slip rings still need polishing by the brushes, too.

Jim, "All my life I wanted to be someone. I guess I should have been more specific."

[TEXAS]

Thanks MR Wizard. That is exactly what I ment. Shut down a unit under a heavy load. You get this. Demand is there but power is dropping. So regulator goes into a boost mode trying to keep up with demand. So unless regulator has roll off protection it burns out. Cost money to replace.

[MEXICOWANDERER]

LPG is excellent for short term use with generators as long as resupply is not an issue. Benefits include running better when cold, absolutely no oil contamination or spark plug contamination. Downsides are increased fuel consumption higher running heat generation and slightly less fuel economy. I would personally NOT run a non-LPG generator for less than a half hour.

[MrWizard]

no a converter doesn't hurt
but the A/C does.. and I think that is what he meant
a heavy induction motor aka a/c compressor produces back EMF

and I'm real sure you know that too, and knew exactly what he meant

RJsfishin wrote:

TEXAS wrote:
Run it at least a half hour a week. Don't let it set for months. If you are on the road and only crank it when you need it each day. You will be ok.Just don't start it or stop it under load. You will burn out the voltage regulator.

Oh yeah?
I know for a fact that shutdown w/ a 1.000 watt converter load don't hurt'm,,,,,,or hasn't in 20 + yrs.

Running for 5 minuted don't hurt'm either.

[Gjac]

I ran mine for 5 mins multiple times for the last several month's with out my usual 1 hr run once a month under load thinking I used it enough. What I noticed was a creamy white foam inside the filler tube and on the dip stick. Ran it for an hr with a half gallon of gas and Seafoam then changed the oil. My conclusion is multiple short uses without a long one will build up moisture in the crankcase.

[Handbasket]

Only thing I worry about on short runs is the inside-the-box muffler. It's stainless steel, but if it does get eaten thru by the water and other stuff in the exhaust gasses, it'd be a bear to replace, and no doubt costy.

That said, I've run all my 2800's for short periods making coffee and such. The current one has lasted for 7 1/2 years, tho' I have replaced the fuel pump & voltage regulator. Start, wait for 2-4 minutes, run the microwave for 2-3 minutes, let it run on for 2-3 minutes, shut it down.

But I make sure it gets a good 2 hour or longer run every month or six weeks to thoroughly dry stuff out. If I don't run it that long from actual need, I do an exercise run with the A/C or a 1500 watt heater. So far, so good except as noted.

Jim, "Experience is what enables you to recognize a mistake when you make it again."

[TEXAS]

RJ Why take the chance. I have six regulators in my junk pile. All burned out by shutting down or starting up under load.