gmedson

Hi Guys- On October 14 I posted a request for information about Classic Old Time Engines, which offered a repro Deezil in the mid-1990s. Turns out that these were made in China by CS and are the same as the Deezils offered later by CS under its own name. Andrew Coholic said that Don Belote ran COTE.

Jack Hiner said that Don offered an American Micro diesel replica and that Arne Hende might have been involved in the project. Rob Mokry said that he thought that the COTE Micros might be the origin of the later-offered CS Micros.

Well, a COTE Micro turned up on eBay last week, offered by Bob Watts. I could see from his picture that it is very different from the CS Micro I have in my collection. Intrigued, I bid on and won the engine. When I received it yesterday, I could see that it certainly was not made by CS! It is a beautiful piece of work with excellent fits and finish. That's right, like Arne Hende would make. A bit of Googling turned up a picture of the AH Micro, http://www.modelenginenews.org/prod/ah.html, eighth picture, and indeed the COTE Micro and the AH Micro are one and the same. Note Dan Vincent's neat display boxes with some of the engines on this page... Whereas the COTE/AH Micro is graceful and well-proportioned, the CS version is kinda dumpy.


Don Belote's instructions say that his is an accurate rendition except that it has a wrist pin at the upper end of the connecting rod instead of the ball socket of the original. The original also had a brass con rod, but I do not know about the repro, since I have not yet made a tool to take the backplate off.

This COTE engine carries a serial number of 83, so there were likely at least this many COTE/AH Micros made. Perhaps 100? I wonder if Don Belote later made arrangements with CS for a cheaper version? If so, was the project completed and were CS/COTE Micros offered? And, indeed, was this the origin of the later-offered CS Micros? Can someone offer further information? Does someone have a copy of a COTE advertisement for their Micro repro?

I have attached some pics-of the COTE/AH Micro CS and also of it with the CS version.

BTW, you can see a video clip of an original Micro running on YouTube, http://www.youtube.com/user/gh210609.../1/mOToV1w4BlU. The clip verifies that the COTE/AH engine is a close copy of the original. Does anyone know who gh is, who posted the clip?

Regards. -Gary

[email protected]

Gary, thanks for the update on the Micro diesel. When I contacted Don by phone the engines were not yet available. I went with Drone diesels and Oliver Jaguar reproductions. Sure is one nice looking engine. Jack

ffkiwi

Gary, Arne Hende engines were usually manufactured in lots of 100 only, so your '83' numbering is consistent. The only exception that I know of is the AH 0.5cc Oliver Tiger, which proved so popular they did a second run, and slightly altered the shape to more closely resemble the Mk3 Tiger.

ChrisM
'ffkiwi'

ifzama

Hello Gary et Al,
I am facinated by the micro diesel engine. What I want to find out is, can it produce electricity? I am looking for information on this engine which is said can produce electricity very cheaply for developing country farmers.
Any information you can provide where I can find a similar engine would be greatly appreciated:
http://www.practicafoundation.nl/pro...sel-base-test/
Can this engine be manufactured easily today? I did contact practica foundation, and they told me they have abandoned their try to remake the engine.
Please reply me at [email protected].
Thanks
Isaac Zama

Recycled Flyer

I think that the Micro Diesel in your web link is nothing like the Micro Diesel shown in post 1.<o></o>
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Making electricity from an 18cc internal combustion engine may be likely but doing the same with a 2cc model aero engine is ludicrous.<o></o>
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Perhaps you may have confused these two very different engines.<o></o>
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Thanks.<o></o>

AMB

If you do the math if that little engine puts out 1/10 hp (guess) that is only .0745KW can not do much with that martin

MJD

My Feedback: (1)

If the farmers were about 2 cm tall and their farms made of a bath tub full of soil, I would say these are a great choice.

MJD

earlwb

There is a major problem with how small a model diesel engine can go to and still burn straight diesel fuel or kerosene without needing ether to aid in its running. The smaller the engine the more ether you need and you have to use kerosene then too.
The micro diesels need even more ether than the larger engines can use to start and run OK. Thus expecting a poor farmer in a rural setting being able to afford buying or even obtaining ether is very problematical.

I suppose its possible that someone could design and machine a heavy duty small engine to run on straight kerosene. But I find it interesting that no one had done so. A small model diesel that ran on straight kerosene and no ether would be hugely popular with everyone. But apparently it isn't possible, as no one has come out with a small model diesel after all these years.

If I remember a company inSweden tried making a small diesel engine for developing countries, but apparently they have shelved their project as they could not get the cost for the engine down enough.
Another company had come up with a small diesel engine powered generator for use by the military troops in the field. But I don't know if they ever got anywhere beyond the prototypes. A soldier already is carry a lot of stuff and adding a small handheld generator to the load is something of a luxury for most.

A few years ago I used a Enya 25 RC diesel to power a small DC motor for generating electricty for a robot I was working on then. but because of the diesel engine it was a outdoors only setup.

Recycled Flyer

Is it the cubic capacity or the lack of injection that makes smaller diesels problematical?

I have always held that it was a problem to atomize the fuel when using straight kerosene without the use of high-pressure injectors, hence using the ether both as a solvent for the oil and kero, and a cold start ignition improver due to the lack of a glow plug.

The ether simplifies the mechanics of an engine greatly at the expense of complicating the fuel chemistry. But I am sure that if someone could reasonably miniaturise injectors enough to be viable on model engines the need for ether would almost disappear.

So it would seem that the smaller the diesel the worse the atomization at the spray bar and the greater the reliance upon the ether contents to run.

Does this seem correct to everybody else?<o></o>

Thanks.<o></o>

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Motorboy

Smaller engine has low heat of compression to ignite and difficult do start the engine without ether, hence pure kerosene or diesel are impossible to ignite in low temperature generated by heat of compression (can run when the engine are heated up before starting the engine). Ether has low autoignition and are neccesary to add in the fuel used as model engine fuel.

gkamysz

My Feedback: (19)

The Practica project was close. The problem is the constraint of money. We also need to be very clear about the differences between injected and carbureted diesels. Injected diesels simply can't be produced under ~4HP( 3kW) per cylinder at this time. The injection system can't be made any smaller and still be practical. It might be possible to miniaturize the piezo-electric injector to get smaller volumes, but I don't know that the system would be practical in size and cost. Carbureted diesels (HCCI) are difficult to operate on simple fuels over a wide range of temperatures and loads. Model diesels (carbureted) with ether blended fuel do well and the props present an acceptable load range.

earlwb

Thanks gkamysz  that was it the "Practica Project"
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http://www.practicafoundation.nl/pro...diesel-engine/

fiery

My Feedback: (2)

The Cosworth AE-1 80 cc diesel UAV engine can be found on this link

http://www.barnardmicrosystems.com/L...e.htm#Cosworth

Recycled Flyer

Would you agree that if the fuelatomizationwas improved (by some new injector technology) then the amount of heat necessary to trigger combustion would be less in the first place?

Or is it purely the lack of swept volume that precludes the raise in temperature?

Thanks.

gkamysz

My Feedback: (19)

Jens was basically saying that you can't cold start a model diesel without ether. Once hot they run OK without ether.

The Cosworth AE-1 at 3.5HP is as small as injected diesels get. I'd like to see the price tag on one of those.

Motorboy

The limited place are size of parts and injection hole to make good atomization, also not possible to make so small in model engine size.

Recycled Flyer

I agree with everything I read so far and thank the above posters for their help and advice.

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I was just thinking out aloud about ‘if’ the atomisation was fine enough and indeed ‘if’ the injectors could be miniaturised enough to be viable then the need for any ether would incredibly lessened.<o></o>
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I have heard of high pressure hydraulic fluid leaks onboard aircraft that have actually caught fire solely due to their finely atomised state and the pressure that its under. And this is with a fluid that was deemed non-flammable under any other condition.<o></o>

So this leads me to believe that the smaller the swept volume of an engine the greater the need for finer atomisation, however this is achieved. And I also believe that it’s the ether content in the fuel that greatly helps in the carburation and dissolving of the kerosene into the oil content as well as providing the obvious low temperature trigger for combustion.

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To sum up, it seems to me that the finer the fuel droplets then the easier it will be to ignite under any condition, whether it’s hot or cold.

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Thanks guys.

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gkamysz

My Feedback: (19)

The in cylinder temperature must be above the autoignition temperature of the fuel in order for it to ignite. This is why full size diesels need glow plugs in cold weather. Full size diesels have no problem with atomization these days. The problem for model size is building and injector and pump that will dispense the minuscule volumes of fuel and atomize them.

High pressure hydraulic leaks do make a fine spray like a diesel injector, but there still must be an ignition source.

Recycled Flyer

I agree but the accidentinvestigatorsfailed to find one and postulated that it may have been chemically related.

gkamysz

My Feedback: (19)

That's possible, but that doesn't really help an engine.

earlwb

Well, if one could build a small high pressure injector that could inject the fuel in a tiny amount into the combustion chamber it may work.
But it is tricky getting a small engine to have 2,000 to 4,000 PSI of fuel pressure for the injector. Do you power the fuel system separately from the engine or is it mechanical in design?
Since fuel is a finite substance and doesn't shrink with the engine size, I could see a injector winding up being as big if not larger than the engine itself.

Now heating the engine may be doable in a low tech way. How about using a magnifying glass lense to focus the sunlight on the engine head so you can get it to fire up? Maybe a metal insert like a glow plug that can store heat better to help aid with ignition.
Maybe even a glow plug would work to some extent.

Now in the Prakica engine project, it looks like they put the fuel tank inside the water jacket, so the engine would heat the fuel too.
heating up the fuel would help with getting it to ignite.
the big ship diesels do that too. they have a heater to heat up the old bunker oil they use out at sea, before it gets sent to the engine.