Idling your diesel for home power. - Page 3 - PeachParts Mercedes-Benz Forum

Jeremy5848 · #31 07-06-2012, 10:25 PM

Long before owning a Mercedes diesel, when we retired and moved to a rural setting 15 years ago, I bought a 7.5 KVA gas/gaso Onan generator (2 cylinder, 4-stroke, air-cooled). It had seen service with the US Army, powering pop-up targets on the tank gunnery range at Fort Hunter Liggett in Central California.

I had it converted to propane (the Army had used gasoline) and installed it next to our propane tank, wired to the house through a 200 Amp manual transfer switch. It can power the entire house. I run it for an hour or two each month just to make sure it still works but fortunately we are still waiting for The Big One.

With the availability today of low-cost high-power inverters and two Mercedes diesels I might not make the same decision today (to purchase a genset).

Jeremy

spdrun · #32 07-07-2012, 01:59 AM

You need an old "hit or miss" engine, that can run on virtually any crap fuel to run your home generator!

5 hp Economy hit & miss engine full power to low and slow - YouTube

smiffy6four · #33 07-07-2012, 07:27 AM

Idling an engine for extended periods is not good for it. Ask any big rig trucker. They always set the idle higher than the base idle if they are going to be parked overnight for instance. Apparently, it has to do with lack of splash lubrication for the cylinder walls & pistons.

I recall a case about some British Leyland trucks that were sent to Africa to run along a 900 mile long beach highway. After a few runs, the engines would seize. Engineers were dispatched to figure out why these proven trucks were crapping out. Seems the constant running on totally flat runs, no turns, no bumps, etc didn't splash enough oil onto the piston skirts, oil holes were drilled into the con rods to squirt oil on the cylinder walls and that cured it.

I don't know how MB are with regard to piston/cylinder wall oiling. Anyone care to chime in? I haven't had one of my MB apart. Yet

Mark DiSilvestro · #34 07-07-2012, 07:55 AM

Quote:

Originally Posted by ROLLGUY

I guess I should think again about selling my 1,500 watt inverter. I have had it for 10 years, and have not used it in at least 5. I thought about selling it a few weeks back, but I think I will keep it now. I do have a 3,000 watt Diesel generator, but the thing is very loud. I usually run it on biodiesel, as it really stinks when ran on pump Diesel. The inverter idea seems like a decent way to go. The question I would have is, how would you keep someone from stealing your car while it is running (especially if you are inside)? I suppose you could pipe the exhaust outside with the car in the garage.

On many Mercedes, one might also be able to disconnaect the vacuum to the engine shut-off pod, and remove the key, so long as the alternator continues charging with the ignition off.
(Maybe I'll check that on one of mine)

After hurricane Isabel in '03, I tried running my 20 CuF top-freezer fridge off a tiny 1000-watt generator and there wasn't enough muscle to start up the compressor. I realized later that my fridge had a heater- element to reduce outside condensation that was still turned on. So maybe if that had been set to the power-saver mode, my tiny generator would have worked.
Come daybreak, I was able to fire up my backup generator - an ancient 2500-watt Tecumseh-powered Homelite. But it's a heavy jobsite model with a small tank, tiny muffler and very noisy!

Since then, I've acquired a couple of cheap Chinese generators (2000 & 2500 sustained watts) from Big-Lots and Aldi, for the houses in Virginia Beach and Alexandria. I've run the fridge, 2 or 3 CF lights, a fan and the TV, from around 8 am to 11 pm. With that, daily fuel consumption has been in the under 2 - 2.5 gallon range.
So far in 5 years, I've used the Virginia Beach generator three times, for a total of about 50 hours. And the one here in Alexandria once for about 18 hours. So despite their allegedly short lifespan, they could last several more years.

In addition to checking/changing oil, I do shut the fuel off, drain the tanks and run the gas out of the carbs before putting these generators away.
I feel extremely fortunate that last week's 'Big-Blow' only killed my power in Alexandia for about an hour, and not at all in Virginia Beach!

Happy Motoring, Mark

smiffy6four · #35 07-07-2012, 09:30 AM

The alternator won't charge with the key off. You would have to supply 12v to the alt. with a bit of wire.

Stevo · #36 07-07-2012, 10:53 AM

I know from running commercial boats that if you run dead slow for long the engineer will soon be in the wheelhouse to find out why you are disrespecting HIS baby/babies. Something about stack fires

I dont think I would have a problem idling my 616 or 617 overnight however.

For emergency power I have a single cylinder, hand crank, 1800 RPM Lister diesel belt driving a 2.4 KW generator. It will run about five hours on a gallon of fuel. Its not enough to run the hot water heater or cloths dryer but its plenty for TV, computer, reefers and lights.

Jeremy5848 · #37 07-07-2012, 12:37 PM

Quote:

Originally Posted by smiffy6four

I don't know how MB are with regard to piston/cylinder wall oiling. Anyone care to chime in? I haven't had one of my MB apart. Yet

Many MB diesels have oil squirters for piston underside cooling; it's possible that these would help lubricate the cylinder walls (I can't quite visualize in my mind what goes on inside the engine). Clearly, Mercedes didn't build these engines to run at idle for days at a time just to operate an inverter. Engines purpose-built for stationary duty no doubt have the oiling circuits to match.

Jeremy

edge · #38 10-31-2012, 12:05 PM

I am asking if anyone is using an inverter to power up a a refrigerator and a space heater during the blackout caused by Sandy. Harbor Freight has a 5000 watt inverter and also a 1500 watt inverter with 3000 watt peak power. Any current thoughts?

rmmagow · #39 10-31-2012, 12:47 PM

What do you think my options would be to connect up my well water pump? It is running 240V and is wired directly to my box. Is this the kind of setup that would be best done with a transfer box? I am going to buy the HF thing for the reefers and other little stuff. My biggest grief is not having the well pump. Sandy only caused me a 24 hour outage but last year we went over a week without power and it was pretty painful. My 300D would have no issue with long idle even if hot. Don't know why I never actually thought of the inverter thing for this.

edge · #40 10-31-2012, 01:05 PM

how many watts inverter are you buying? Let us know how you make out.

rmmagow · #41 10-31-2012, 03:01 PM

I have found a LOT of information with a little searching around. I plan to get an HF inverter to help provide power for lighting during a power outage but I have found that what I really want is a Reliance transfer switch and about a 7500 Watt generator to really run my house during a major outage. Small but interesting side effect will be that with 7500 Watt generator I would be able to run a two post lift in my garage while planning on how to extend a 240 setup into the garage with a new breaker box. I'll be spending upwards of $1500 for the generator and transfer switch but feel it will find itself being used at least three times a year for emergency power. I've kind of settled on a propane fired generator but I'm not 100% there yet. Diesel might be an option or standard gasoline fired unit. Transfer box connects a lot easier than I thought too.

Silber Adler · #42 10-31-2012, 03:13 PM

Something to keep in mind is that a w123 alternator is only what 70 amps or about a 1000 watts.

It would take more than an idle speed to get that much out. Probably half of that at idle would be all you could sustain with out discharging the battery. Of course if your refrigerator was starting it might go over that for a few seconds then settle down.

We put electricity into our farm house this summer. Ran it on a coleman generator some solar cells and a deep cell battery with inverter before that.

The constant heat this summer drove us to the power company. We of course have had power at our business forever. We proved that we can be without and survive though.

pwogaman · #43 10-31-2012, 08:36 PM

I bought a DoD surplus 500 pound 5kw gas generator since my last post earlier in this thread. We lost power for about 1 3/4 days because of Sandy and I used this new to me generator. While the generator has more capacity than my 300SD inverter set up, it is a heck of a lot louder (an air cooled 20 hp engine running at 3,600 rpm) and it is a hell of a lot guitarist, consuming over 1.3 gallons an hour. The 300SD used about .5 gallons an hour running at 1,100 rpm.

So . . . unless I need the extra capacity, such as for the washer/dryer or 240 volt A/C, I'm going to use the inverter next time.

cornemuse · #44 10-31-2012, 09:13 PM

The company I spent most of my career working for had a couple of ooold pieces of equipment with cat motors with hand crank pony starter motors, it seemed always started better when it was cold. If we thought we might use one, we started them/it 1st thing at 7:00am, and a lot of the time they idled all day, and occaisionally all nite too. It never seemed to hurt them tho. One Manitiouc(K??) dragline (1948, a year younger than me!) had a cat motor about 8 feet long redline 1200rpm! I dont think it used a gallon idling for 8 hours. -corne-

dieselmania · #45 10-31-2012, 09:32 PM

I have read that some diesel engines (like the Powerstroke) are prone to wet stacking when iding, and should not be idled without an idle speed control to keep cylinder temps up. I have not heard any issues with wet stacking on any Mercedes diesels, anyone else?

PS There was a story some time ago about an airline stewardess that worked out of O'hare and would leave her Benz idling in the employee lot while she was out on winter flights.