Any Love for Air Cooled Diesel Generators?

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Best F100

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Happy New Year.

Recently bought an air cooled, diesel generator from a government auction. Something to "play with". In this case, It is a 3KW, Wisconsin Robin powered unit. Model # WRDI-270. Open frame, weight about 170 lbs. Japanese engine. 200 hours. Used by the Air Force. Bought at a great price. Never owned a diesel generator, so I want to know the following:

* 1) What can I expect at fuel consumption at 1/4 load and full load, as compared to a 3kw Honda EU3000is (which I also own)? Diesel cars have about a 30% advantage over
a gasoline fueled counterpart. Any advantage here? Or over a typical. 3kw gasoline generator?

* 2) What can anyone tell me about engine longevity over gas generators? I have a used Honda EU6500is bought from a steel company with 3600 hours - runs like new.
Standby power for my house now. I do not know how it was previously maintained. Can I expect over 1000 hours?

* 3) From what I understand, Yanmar made/makes a durable air cooled generator. The Chinese made clones, not so good. Anyone own one? That may be a future purchase,
after I get rid of one. (Got to thin the herd).

* 4) Can I expect a greater, startup surge capability for this generator, over a gasoline version of the same KW? Diesel trucks have more torque than their gasoline counterparts.
Can I expect something like 4 - 4.5kw startup surge capability & 3kw at constant operation?




Before I forget. At the same auction, I saw with my own eyes, the equivalent of seeing a "Bigfoot" or Sasquash. Two Honda EB12D DIESEL generators were sold. 12KW. Liquid cooled. Door enclosures on 4 sides. (Google it to see what I am talking about). One with only 2 hours on it. The other with 94 hours. Impressive machines. Each weighing over 900 lbs. I could not pick up one corner of this generator. I would have great difficulty getting them in and out my pickup truck - even if I had the cash to pay for them. Sold for just under $3000 each. Also, former, US Air Force generators. Last sold to the public about 10 - 12 years ago. We should all lobby Honda to bring them back to market. A lot of folks would break their kids piggy bank, to have an updated, inverter, diesel version of this generator - if we don't have our dreams, what do we have? We all have to get ready for the coming Russian attempt to knock out US power grids.
 
I do not like inverter gens, when the circuits boards break, to expensive are those parts. To me they don't define robustness.

Is your gen putting out a standard useful household voltage and frequency?
 
We used air cooled diesel gens in the army, I used them a lot, but can't remember much about brands, power etc. They were green colored if that helps.

They were heavy (for man portable units) and noisy and a decent pull to start. But they always did start and always did work even though they were a bit on the old side. I thought they were good on fuel, as I didn't have to top them up much. We had ours going for days on end.

Hard to sleep next to when they put your pit beside one and it's on all night running the radio comms. Then it probably started to rain.

Those air force ones are so the officers can use their electric blankets on a cold night, and their coffee grinders in the morning. (Just joking my AF brothers )
 
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Originally Posted By: sdowney717
I do not like inverter gens, when the circuits boards break, to expensive are those parts. To me they don't define robustness.

Is your gen putting out a standard useful household voltage and frequency?


This Q +2. I thought a lot of these surplus generators put out 36 VDC for "light-alls" which would take some handiwork to make otherwise useful.
 
Originally Posted By: Best F100
Happy New Year.

Recently bought an air cooled, diesel generator from a government auction. Something to "play with". In this case, It is a 3KW, Wisconsin Robin powered unit. Model # WRDI-270. Open frame, weight about 170 lbs. Japanese engine. 200 hours. Used by the Air Force. Bought at a great price. Never owned a diesel generator, so I want to know the following:

* 1) What can I expect at fuel consumption at 1/4 load and full load, as compared to a 3kw Honda EU3000is (which I also own)? Diesel cars have about a 30% advantage over
a gasoline fueled counterpart. Any advantage here? Or over a typical. 3kw gasoline generator?

* 2) What can anyone tell me about engine longevity over gas generators? I have a used Honda EU6500is bought from a steel company with 3600 hours - runs like new.
Standby power for my house now. I do not know how it was previously maintained. Can I expect over 1000 hours?

* 3) From what I understand, Yanmar made/makes a durable air cooled generator. The Chinese made clones, not so good. Anyone own one? That may be a future purchase,
after I get rid of one. (Got to thin the herd).

* 4) Can I expect a greater, startup surge capability for this generator, over a gasoline version of the same KW? Diesel trucks have more torque than their gasoline counterparts.
Can I expect something like 4 - 4.5kw startup surge capability & 3kw at constant operation?




Before I forget. At the same auction, I saw with my own eyes, the equivalent of seeing a "Bigfoot" or Sasquash. Two Honda EB12D DIESEL generators were sold. 12KW. Liquid cooled. Door enclosures on 4 sides. (Google it to see what I am talking about). One with only 2 hours on it. The other with 94 hours. Impressive machines. Each weighing over 900 lbs. I could not pick up one corner of this generator. I would have great difficulty getting them in and out my pickup truck - even if I had the cash to pay for them. Sold for just under $3000 each. Also, former, US Air Force generators. Last sold to the public about 10 - 12 years ago. We should all lobby Honda to bring them back to market. A lot of folks would break their kids piggy bank, to have an updated, inverter, diesel version of this generator - if we don't have our dreams, what do we have? We all have to get ready for the coming Russian attempt to knock out US power grids.



Those honda diesels were absolute gems.

Love the air called diesel stuff but without a significant flywheel it wont have much more kick than an equivalent gas genny.

Heres one consumption chart but the sizing isn't perfect for yoru application.



http://www.barringtondieselclub.co.za/technical/fuel-consumption.html
 
A small diesel generator would be pretty cool. Really any small diesel would be cool (generators, bikes, etc).

I don't know if this is true, but is jet fuel and diesel compatible? I assume that's why the AF/military uses diesel generators?
 
I posted a list about generator efficiency on another board. The Honda inverter generators are universally poor at high loads.

As you might expect, a good conventional generator head is about 90% efficient at 80% load. Inverter circuitry adds some loss, to the non conventional generator "head" .

The Honda's advantage is fuel savings when lightly loaded or unloaded. As the engine slows down to idle, reducing friction. However, the overall efficiency when producing any substantial amount of power is lower than many people expect.

Here are some numbers: (note, look at KWH/gal, higher is better)

Honda EU2000i inverter generator

1,600W 4.75 kWh/gallon Run time 2.97 hours/gallon.
555W 4.47 kWh/gallon Run time 8.06 hours/gallon

The Honda is almost as efficient at low loads as it is at high loads. This is fantastic when you need very little power. But it's not as good as a conventional genset at high loads, as we will see below.

Generac GP3250
2300W, 5.53 KWH/gallon
1900W, 5.35 KWH/gallon
1150W, 4.45 KWH/gallon
744W, 3.84 KWH/gallon

Yamaha EF3000is
2300W, 4.50 KWH/gallon
1900W, 4.42 KWH/gallon
1150W, 4.38 KWH/gallon
744W, 3.89 KWH/gallon

Notice the inverter Yamaha is not better than the Generac until it's at 1/4 load or lower. At which point, you will save fuel.

Listeroid 6/1 diesel with belt drive ST generator head (notice that it's twice as efficient as the Honda/Yamaha inverter generators when heavily loaded, and exceeds the inverter's efficiency all the way down to 500W) (at which point, it consumes about 1/10 gallon per hour, on par with the Honda)
3000W, 8.57 KWH/gallon
2000W, 7.69 KWH/gallon
1000W, 5.71 KWH/gallon
500W, 4.2 KWH/gallon Run time 8 hours per gallon (exactly the same as the Honda, this showcases the diesel's efficiency)

15000W Generac portable (gasoline) (note, the bigger the generator, the more efficient)
15KW, 8.3KWH/gal
7.5KW, 5.9KWH/gal
3750W, 3.8KWH/gal

30,000W John Deere turbodiesel generator (note, diesels are often very efficient at a wide range of loads, and sometimes worse at very high loads)
30KW, 11.4KWH/gal
15KW, 11.5KWH/gal

200,000W JD turbodiesel generator
200KW, 15.5KWH/gal
100KW, 15.5KWH/gal (or roughly 20c/KWH at $3/gal) (still double the local utilities price, and the unit's capital costs are enormous)


I have no idea what efficiency your little diesel will achieve. But I think you can look up engine BSFC numbers and expect the generator head to hover between 80% and 90% efficient depending on load. Making half load, I'd expect it to be more efficient, per gallon, than the Honda by a bit.
 
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A place where I spend a good amount of time, and where generators of size are truly needed, diesels are the only option (USVI).

Nobody runs off of LPG (which is used for cooking) or gasoline if they can avoid it. Far too inefficient. They've learned that lesson from times when power was out for weeks or more. My wife lived nearly a year off a generator after a hurricane. You learn how to load manage and what you really need to run...

Now, inverter generators offer a substantial benefit - no need to run at 3600RPM, you can vary RPMs, and get higher power density at high loads (smaller engines) and less fuel consumption at light loads (lower RPM). Even the big industrial diesel genset makers are moving that way... But you still need a low SFC generator, which means diesel...
 
Great data Cujet. ohhh a lister..... love love love them....

Id guess the OP's Honda will easily make 7500 and maybe 10K hours.

An 1800RPM diesel can last tens of the thousands of hours if properly cared for.

There is a guy out there claiming his Ef3000 has 30K hours on it and only needed rings. Not sure I believe that but they can run a long time

Whatever genset you have dig into the manual and take a look at the valve lash inspection hours- that will tell you just how high a quality the material in the head and valve train are.
This is the most commonly ignored maintenance item and the one that sends the inexpensive units to the trash bin all the time.

The Generac GP 3250 and many other open frame units has a 100 hour inspection interval and the Yamaha a 300 hour interval - if one follow this maint item, the ownership cost in terms of invested hourly maintenance becomes a gigantic difference between these 2 units.

UD
 
Originally Posted By: Best F100

Recently bought an air cooled, diesel generator from a government auction. Something to "play with". In this case, It is a 3KW, Wisconsin Robin powered unit. Model # WRDI-270. Open frame, weight about 170 lbs. Japanese engine.


F100, Is yours a MEP-016D? It probably has the same Yanmar L70AE engine mine has.

Originally Posted By: Donald

How are the glow plugs powered if it has them?


Donald, no glow plugs - it uses an air intake heater grid (24 volts)
 
Originally Posted By: Linctex
Originally Posted By: Best F100

Recently bought an air cooled, diesel generator from a government auction. Something to "play with". In this case, It is a 3KW, Wisconsin Robin powered unit. Model # WRDI-270. Open frame, weight about 170 lbs. Japanese engine.


F100, Is yours a MEP-016D? It probably has the same Yanmar L70AE engine mine has.

Originally Posted By: Donald

How are the glow plugs powered if it has them?


Donald, no glow plugs - it uses an air intake heater grid (24 volts)









No, Linctex. Not the same generator as yours. I had to look up a MEP - 016D generator to see what that is. That is a nice generator you have. No two people are going to pick yours up and walk away with it, because I bet yours weighs 400 lbs. Yanmar has a quality reputation. I have a WRDI - 270 model. Only weighs no more than 170 lbs. Used by the Air Force and Navy. Made by T & J Manufacturing, out of Oshkosh, WI. Also sold by the Power Gard Generator Brand Name, I believe. Google, "WRDI - 270 generator" and look at the images.

As I said before, mine has a Robin (Subaru) engine. Many equipment rental places use Robin engines. They are supposed to be on par with Honda engines. 3 kw. single phase. Glow plug/manifold heater. Both rope start & electric start. (Wife won't use rope start, so electric start is a plus). Twist lock 120V plug with a 30 amp design. Unlike my Honda EU 3000is, it also has the 240V plug. However, with just 3kw to work with, I am not sure what 240V items, I can repower in my house. Surely, not the electric water heater. Maybe an electric stove? Not sure how many watts they use up.

I bought it (for only over $200), because Subaru says I can still get most engine parts. I was also looking for a diesel generator that sips fuel (and could potentially run all night). Runs at 3600 rpm. 1800 rpm generators are not in my budget. The plan is to feed it, the finest 15W40 or 5W40 money can buy, and see how long it holds up. If it was good enough for Air Force and Navy usage, it should be good enough for residence back up duty.
 
The Robin Subaru is every bit the equivalent of Honda. They make fantastic gensets.

If the OP has a genuine Yanmar he's set.

UD
 
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