http://www.modelenginenews.org/faq/index.html.  Search for "fuel".

Somewhere on the modelenginenews.org site there's a treatise on model diesel fuel that should shed some light.

You can buy it from Davis Diesel, and there's another company in the US that sells it -- it's mentioned in the above FAQ.

My best suggestion would be to get a copy of "Dr. Diesel's Diary", by Eric Clutton. About $12. It won't deal with the DC specifically, but is the best collection of diesel info, tricks and tips I've ever seen!

http://www.cafes.net/doctordiesel/      (Under "Accessories")

  Thanks guys, but what i really want to know i guess is, will it perform well on say a baby ringmaster, or maybe a little skyray or the like. I guess another way of puttin it is how does it compare to various glow .049's?

Probably about the same as a Black Widow, but with a different prop.  I would go for a 6x4 or 7x3.5 prop compared to the 5x3 that would be ideal for the BW.  You will get about the same speed, but much better "pull" through the overhead maneuvers.  You want to set it to very slightly go " brpp brpp brppp" in level flight and clean up when you hit the maneuvers.  Try to find a setting where you don't have to touch anything before launching.  Diesels are unbelieveably sensitive to needle as far as fuel consumption is concerned.  Mess with the compression to get it started, but leave the needle alone!!!!!! 

Larry, thankyou!!!!! Thats what i needed to know. I have downloaded plans for a baby ringmaster to build for it. I would be cuttin wood already but i dont have a printer. I have put the plans on a flash drive and gave it to my son for printing. He forgot last night.

I've had two Super Merlins and only run them on the bench.  Both ran well and seemed to be moderately powerful.  I sold one, and still have the other.  It suffered from a loose compression screw, so I tapped the head for a 4-40 set screw, which works fine.  My general thinking on diesels is that you leave the needle alone, because, as said,   the needle is more sensitive in terms of run time than on a glow engine.  In general, I adjust the compression and needle until the engine is running fast and smooth, with clear to honey-colored exhaust.  I like the engine to run smooth in level flight and through maneuvers.  If it loads in maneuvers, it is overcompressed, if it misses in maneuvers, it is a hair lean.  Ideally, the engine starts on running settings, and I have used a starter.  Some diesels won't do this, and you have to change the compression to start them, either up or down, depending. I'd strongly recommend using commercial fuel, so that fuel is not the problem.  I've used both Davis and Eric Clutton fuels.   

Hi,
   As far as running is concerned Larry's recommendation for props is spot on, but I agree more with Jim about setting up the engine. I am a touch surprised about both gentlemen's advice to leave the needle alone. My diesel experience has been that you have a fair latitude in needle setting, but I am not going to start an argument. For the small DC engines, Dart, Merlin, Spitfire and Sabre, two and half turns on the needle is usually not too far from the running setting, with perhaps a quarter turn either way from best setting, not unduly affecting the run.
  Your one third fuel formula is what I normally use on this type of engine and maybe 1 to 2% of ignition improver, isopropyl nitrate is the norm over here (IPN). This latter addition makes the needle far less critical and could be the cause of both Larry and Jim saying that needle setting is critical.
In the old days (50 years ago!), a youngster could go to a chemist (pharmacy) and buy amyl nitrate or nitrite, provided you had a letter from your parents. Not much chance these days with the drugs scene as it is!
  I don't know if this is true, but one of the two main model fuel mixing companies, claimed that the existing stock of IPN had run out. It was apparently used as a means of starting the English Electric Lightening interceptor jets (maybe someone can explain how this works?). When they were withdrawn from service one of the companies (or both) purchased the redundant stock. British diesel fuel relied on this stock for many many years. When it ran out, there was a scramble to find a company willing to make the stuff. A company was eventually found to do this, so the Brit diesel freaks are safe again!

Best wishes,

Andrew.

P.S. Use only good first pressing castor if you can get it and DO NOT go much below 30%. Even with oily kerosene it is easy to get too little lubrication. The other reason is that a higher oil content will give you better compression if the running fits are not too good! It gets more difficult the smaller the engine and much below 0.5 cc, you may be well advised to increase the ether and reduce the kerosene. I would recommend you buy commercially. Dr Diesel or Carlson's Engine imports should be able to sell you the correct fuel if you tell them what engine it is for.