Kubota G5200 / D600 for generator project

[Thob]

I've seen a couple of the Kubota G5200 "lawn tractors" for sale locally on Craigslist at what seem to be good prices.  I'm thinking of getting one of them for a generator project.  My understanding is that they come with a D600 Kubota 3 cylinder engine.  I think I could couple the engine to an ST-5 generator head and produce around 4kW of power.  I may either set it for direct drive at 1800 RPM or belt drive at 2200 RPM (engine speed).

Questions:

1) Is there anything needed to be done to the injection pump to set it up for generator use?  I'd like to use the built-in governer for engine speed (if there is one).  Since the engine is setup for variable speed, I need to know if there is anything required or recommended for constant speed operation.

2) Does anyone have a decent, but inexpensive electronic speed control?

3) Any major reason not to convert this engine to generator use?

Thanks -

[Henry W]

The D600 is a very nice little engine. But it needs to be ran at higher speeds than you are thinking of running it.

They are a high speed engine and are designed to run between 2600-3600 rpm. Max torque is at 2600 rpm. It is best to run them past peak torque by a hundred or two hundred rpm. I would belt drive it so the engine would run at 2800 rpm. It should run fine for a very long time. If you decide to run it slower you risk accessive vibration and stress on critical engine parts because the D600 is not spec'd to run at low speeds.

If you want a slower speed engine I would recommend a D905 or D1005 engine. They can be set up to run at lower speeds. http://www.microcogen.info/index.php?topic=1743.0

Henry

[Henry W]

I was in a rush when I last posted and I could not answer some of your questions.

Timing of the injector pump is not needed if you run the engine at 2600 RPM and up. Running it slower, it might have to be retarded some.

The Governors are pretty good from 2600 rpm and above. Any slower I don't know.

No reason not to use this engine for generator use. I know a generator manufacture that used some of these quite a while back and they set them up to run at 2800 RPM. I hear they ran very nice at that speed. The newer super mini series engines are the engines that replaced the D600 and they pretty much have the same characteristics on how they run. My experiance with the Super mini series engines is they seem to run very smooth at 2800-3200, At 2600 rpm they still run good but they are not as smooth and had more of a diesel knock. At 3600 RPM they seem a little stressed out. I think this is why the engineer I know that designes generators that use the super mini series engines like 2800 rpm.

Henry

[Thob]

Henry,

Thanks for the advice.  The seller lowered the price, I better jump on it before he gives it away free!

[Henry W]

Go for it.  Let us know how it works out.

[Henry W]

Some videos!!

http://www.youtube.com/watch?v=R6UAJZek_NM

http://www.youtube.com/watch?v=gyDHS22J4mw&feature=related

1. The engine is very noisy at 1800 rpm. Pretty loud fuel knock.
2. Engine governor cannot maintain 1800 rpm. Needed differant mechanical governor.
3. Serverly overloaded @ 5000 watts.

He could of avoided all this if he ran the engine at 2600 - 2800 rpm. And the engine would live a much longer life.

[Apogee]

Don't know what you use to mow with, but I would NEVER scrap one of these mowers.  They are AWESOME!

Far, far better than 95% of what is currently available.

Just my $.02,

Steve

[Thob]

I brought it home on Saturday.  It doesn't have a mower deck, my guess is they wore the deck out and saved the tractor.  The owner said they used it to tow trailers around.  It has 6500 hours on the clock, starts and runs OK.  The temperature gauge appears to work but I don't think the low oil pressure light or glow plug indicators work properly.  Engine is a little grimy but no worse than I would expect.  Both front tires are totally shot, one of the rear tires is nearly slick and only holds air for about a day.  The other rear tire looks pretty good.  I'm not planning on removing the engine at this time, but instead mounting a generator head somewhere on the frame and running a belt to the engine.  There's a two-sheave pulley on the flywheel end of the engine, I believe this was to power the mower deck and front attachments (tiller or snow blower?).  The engine is mounted "backwards", with the radiator next to the steering column.  Which makes a lot of sense for this application!  I'm currently thinking of mounting the generator head below the frame and sticking out front, with belt(s) running up to the engine.  It may not fit there (not enough ground clearance?).  I'll mount it on the side if I have to.  Eventually I may replace the v-belt with a serpentine belt but for now I'll play around with various size pulleys and v-belts.  The plan is to have a self propelled generator that I can drive around the place to where-ever I need power, or down to the house as a backup generator.  Who else has a generator with hydrostatic drive?

Not a bad deal for $200.

[Henry W]

You did very good.

Henry