Reduced speed Yanmar clone genset

[piperpilot3tk]

Looking at the possibility of putting together several reduced speed yanmar clone gensets similar to the one Central Maine Diesel sells.  For those unfamiliar with the CMD unit here is a link http://www.generatorsales.com/order/yanmar_4kw.asp?page=yanmar_4kw.

Looks like this unit is set up to run the engine at reduced engine RPM, probably somewhere around peak torque while relying on pulley ratio to obtain 3600 shaft RPM on the alternator.

There are many brands of Yanmar clones available at different price points, and it seems impossible to tell which would be best.  Same problem with the genhead, I think it would be best to use a two pole unit as it would make pulley selection easier, but I am struggling to find any suitable two pole two bearing genheads that appear to be well built.  Then there is the problem of finding pulleys that will fit the engine and alternator.

Looking for any suggestions for sourcing parts and advise concerning durability of the various brands.

Thanks, Mike H.

[piperpilot3tk]

Looking at the engine specs for the Chinese L100 clone it appears that 2000 RPM would be the best engine speed.  At this speed the engine makes 8 H.P. and consumes 250 g/kw-h of fuel.  This could be a cool project if a decent inexpensive alternator could be sourced.  Cheapest one I could find that would probably be reliable would be an ST.  Even with an ST the total cost would be approaching the cost of a complete Chinese diesel genset, and would only be worth the time and money if the fuel burn and overall unit reliability were better than the commercial units.  What do you guys think?

[veggie]

They are careful to not state the engine rpm.
At best, they may have slowed it to 3300 otherwise it can't make the power they claim.
The engine is a 408cc, L100. It puts out 10hp @ 3600 rpm
They advertise the generator package as a 5kw unit.
To make 5kw they need the full 10HP ------> or 3600 rpm. ??
They state a continuous output of 4.5 kw which would require 9HP, so its not evident how they do it with a "slower speed".

I slowed my L186 , 418cc generator to 2500 rpm and the best it can do is 4kw before putting out black smoke.
So, how is this possible that they have a 5kw gen set with a slow speed 408cc L100 ?
Not saying it's impossible, but it doesn't make any sense to me  

I too wanted to use a high speed diesel and slow it down. Here's how it turned out...
http://www.youtube.com/watch?v=dXy6uQBj7YY

veggie

[veggie]

Here's the perf curve for the larger L186, 418cc engine.

3500 rpm = 10hp
2500 rpm = 8hp
2000 rpm = 6.5hp

(and that's at sea level)

veggie

[piperpilot3tk]

I agree that the power output numbers for the CMD unit do not seem possible, but the concept is interesting.  The "L100" clone I am looking at is rated for 10HP so maybe it is really a "L186".

Veggie, you're set up looks great!  What kind of alternator is that?  What is the fuel burn at 4kw?  Are you happy with the unit?

Thanks, Mike.

[Apogee]

Mecc Alte heads are decent, lower priced heads.  They're made in Italy, not China, and are from a real manufacturer that is similar to Marathon in quality. From the link you posted, Mecc Alte is also what CMD appears to be using.  You might contact them for pricing on the genheads.  They're good guys!

Some other sources:

http://www.brandnewengines.com/generatorheads.aspx

No, I'm not associated with the above company in any way.  I simply searched eBay, found them, and linked to their site because their prices seemed reasonable.

Northern Tool also carries them just branded under their own NorthStar name:

http://www.northerntool.com/shop/tools/category_generators+generator-heads

I have bought multiple Mecc Alte heads and have been very pleased with them.  When I bought mine, I was trying to find something better in quality than the ST variants, and Mecc Alte had the best quality to price point that I was able to find.  Copper windings, brushless, good bearings, metal fan, low distortion, manufactured in an ISO 9001 plant, good parts availability, etc.  Real products built by a real generator head manufacturer that's been in business for a long time.  I really wanted US made, but wasn't able to find anything for a reasonable price.  The US variants are Baldor and Marathon and both are brutal from a pricing perspective.

Below is the model that I have several of.  I'm sure any of the others would also be fine.  I do like that the other models that have the outlets already installed.  It would be very convenient if building a portable/semi permanent unit to have the cord is easily detachable.  Would minimize wiring hassles and the installation of a separate breaker/output box.  In hindsight, it would have been easier and would have saved about $100 when all was said and done.

http://www.brandnewengines.com/S16F-180BD.aspx

Keep in mind that the models that I've linked to are 3600 RPM, 2 pole heads.  They also make 1800 RPM, 4 pole heads but they are more expensive.

Good luck with your project!

Steve

[veggie]

I agree that the power output numbers for the CMD unit do not seem possible, but the concept is interesting.  The "L100" clone I am looking at is rated for 10HP so maybe it is really a "L186".

Veggie, you're set up looks great!  What kind of alternator is that?  What is the fuel burn at 4kw?  Are you happy with the unit?

Thanks, Mike.

Hi Mike,

The head is a "Voltmaster" from Wanco in Colorado.
Fairly good quality.
They have dealers all over the USA.
Model is AB50 and is rated at 4kw continuous (5kw intermittent).

I'm quite happy with the unit. I think the engines are very well built and quite reliable.
My father now has this unit as a backup power system.

keep us posted of your progress (and post pictures or a youtube vid),
Veggie

[veggie]

The Voltmaster is sold at the place that Steve posted above.
Look on this page.....
http://www.brandnewengines.com/generatorheads.aspx

Not a bad price.

veggie

[Apogee]

Veggie,

Just checked out the vid of the unit you built.

Nice job!  Very clean.  I also really like the belt cover.

Excellent work!

Best regards,

Steve

[veggie]

Apogee,

Thanks for the kind words.
It's a very simple unit.
Engine, Belt drive, generator head.
The belt drive is sized to run the generator at 3600 when the engine is running at 2500 rpm.
My concern was noise and engine life.
A big bonus with these air cooled diesels is that they come with starter motors.

veggie

[piperpilot3tk]

Thanks for all the information guys!

[cujet]

From looking at the various published fuel consumption curves, 2700 RPM seems to be the ideal number for those engines. With 2500, not far off.

If the belt drive is efficient, there are savings there. Regardless of total maximum output.

The clone engines used to have a history of failures. Some internet pics show the counterbalance shaft causing case cracks. Some show broken connecting rods. In any case, the reduction in RPM is very likely to result in much reduced risk of structural failure.

I like the idea of a clone powered genset very much. I have no problem with 3600 RPM heads, and I suspect that there is no difference in lifespan when quality 1800RPM vs. 3600RPM heads are compared.

In fact, the published fuel consumption numbers are lower than the listeroids!

Veggie, are you seeing excellent fuel consumption numbers? Very nice set up!

[veggie]

Cujet,

Sorry, I can't offer much in the way of fuel usage data. I have never checked.
I would not be surprised if the specific fuel consumption was lower than a roid. More modern design engine and direct injection.

veggie

[neelix]

I have a 418 running at 3600 and I would love to slow  down to 2700. Where did you get your pulleys? If I am calculating correctly I would need a 5 inch and 4 inch pulley.

Nice job...

Rob

[veggie]

Neelix,

The pulleys are available at any Power Transmission supply store.
Tell them the desired speed of your engine and the speed of your generator head, HP, and shaft sizes.
They will calculate the best drive for you.

veggie