diesel engine choice

As regular readers will maybe already know, I am interested in Noblers with a Fox 35 (because that was my goal when I first started CL in the seventies) and 2,5cc diesel engined stunters. This is because I made my first loop in 1978 with a beautifull but too heavily built flapped fifties Dutch design 'Mickey' with a weak Enya glow 15-III. I wanted to have diesels then, but they weer not sold in my modelshop then. Since I started again, I collected five 2,5cc diesels, three weer new, a russian UCTKAM (front intake, side exhaust), a PAW Single ball bearing, a chech MVVS (front intake, side exhaust), a chinese CS (silver swallow) front intake, all round exhaust) and two secondhand, a (chech?) FOK (front intake, all round exhaust) and a russian MAP3 (rear intake, all round exhaust) and I want to build a Mickey again. Wingspan is 94 cm (37 inch) and wing-area is 16,2 dm2 (259 square inch?) I have run the UCTKAM and the CS on combatters (as stunt trainers, not competition). I'm very impressed with these engines. They run much better and faster than my old Enya ever did. The UCTKAM however seems more like a speed engine (Teamrace?) and starts to hesitate in manoevres, whatever the setting. I have only ran in the PAW and the MVVS. I think the are too heavy and will have much too much power for my little stunter. The plan gives (besides two dutch designs) the following engine suggestions: Webra Mach 1, ED racer, Allen Mercury 25 and Elfin 2,5. Which of my engines will compare best with a stunt-diesel of the fifties? What should I look for in a diesel that I want to use in a little fities stunter? I a thinking about this choice for one and a half year now, and still have not decided. I only made the choice more difficult by buying more engines. What's your opinion? PP

I've not had experience with the engines you have in hand except for the MAP 3. It is more powerful than an ED Racer. I'd think the CS or the PAW would be your best choice. The airplane you describe is a little small for a good 2.5 diesel, but should be OK if you can build it light enough. I'd suggest being ready to lengthen or shorten lines to get an appparent airspeed you can live with. I'd also start out with a 9 x 4 propeller.

>I collected five 2,5cc diesels,
>three weer new, a russian
>UCTKAM (front intake, side exhaust),
>a PAW Single ball bearing,
>a chech MVVS (front intake,
>side exhaust), a chinese CS
>(silver swallow) front intake, all
>round exhaust) and two secondhand,
>a (chech?) FOK (front intake,
>all round exhaust) and a
>russian MAP3 (rear intake, all
>round exhaust) and I want
>to build a Mickey again.
>Wingspan is 94 cm (37
>inch) and wing-area is 16,2
>dm2 (259 square inch?) I
>have run the UCTKAM and
>the CS on combatters (as
>stunt trainers, not competition). I'm
>very impressed with these engines.
>They run much better and
>faster than my old Enya
>ever did. The UCTKAM however
>seems more like a speed
>engine (Teamrace?) and starts to
>hesitate in manoevres, whatever the
>setting. I have only ran
>in the PAW and the
>MVVS. I think the are
>too heavy and will have
>much too much power for
>my little stunter. The plan
>gives (besides two dutch designs)
>the following engine suggestions: Webra
>Mach 1, ED racer, Allen
>Mercury 25 and Elfin 2,5.
>Which of my engines will
>compare best with a stunt-diesel
>of the fifties? What should
>I look for in a
>diesel that I want to
>use in a little fities
>stunter? I a thinking about
>this choice for one and
>a half year now, and
>still have not decided. I
>only made the choice more
>difficult by buying more engines.
>What's your opinion? PP

I think that the Silver Swallow followed by the PAW will be closest to the the AM 25 but in reality you can always alter the power output of your engines by reducing the compression or running them rich.

If you want to built a nice flapless stunter you could build Blue PAnts by Henri Stouffs, it's a winner and can cope with any of the engines that you have.

Regards

Thanks for the advice. Problem is that I'm still learning how to use these diesels as I have no-one to teach me. I tried to tame them by setting them a bit undercompressed or rich, but then they just don't run dependable enough to give a good 'stunt-run'. I think I will choose the CS as they are still sold new, are cheap, light and run very well. They maybe won't last long, but I can always order a hand full of new ones. The only problem with the PAW is it's weight. This weekend I will attend the British Nats and I want to buy a PAW 1,5cc to see if this is comparable with the CS for weight and power. If it is, I think I will try the PAW 1,5cc.

I'm in the same position you are--no one to help me with diesels. I make the most progress when I concentrate on one engine and fly it and fly it until I have some understanding of it. Individual diesel engines seem to me to be more different than a similar group of glo engines. But that is because I understand glo engines better, I think.

I try to adjust compression and needlevalve for power and reliability, and then regulate speed and line tension with prop selection and line length. I like the white Tornado props. They seem to run smoother on my diesels than other props.

PP and Jim T.,

One of the best sources of diesel information is "Dr. Diesel's Diary" from Eric Clutton (phone 931-455-2256). Eric explains all the ins and outs of engines and fuel. Wish it was available back in the 50's when I was learning diesels. It would have saved me a lot of bloody and aching fingers.

you could use an os20 fp with a davis head lots of power, cheap to run and still available