David Cooke 1 Posted April 4, 2016 Share Posted April 4, 2016 An old boss has given me some of his father's RC engines to enjoy. TBH I'm a small 30-36" vintage builder so not sure I'll get use out of the bigger .40 engines. After 20 year gap I just use brushless and last used an IC as a teenager. I'd like to get this little DC engine going. I know nothing of diesels. Can someone identify the engine? Its a 6x3 prop and weighs about 42g with the prop. I'm planning on soaking in glow fuel then disassembling and cleaning. I'm unsure what fuel to use (where to get it) (I know its a "diesel". What is the port on the back of the crank for? Is a fuel tank supposed to go there? Unlikely I can get one these days. Fuel presumably goes into the carb - that little bit I do remember as a kid Thanks David Quote Link to comment Share on other sites More sharing options...
brokenenglish Posted April 4, 2016 Share Posted April 4, 2016 Hi, The engine you have is a late production DC Dart, 0.5cc. Without wishing to discourage you, some of the late production (the company changed hands) were pretty awful, and many were non-runners as sold, when new! However, yours looks like its been run a bit, so presumably it runs. As you surmised, the tank is missing, and the tapped spigot in the backplate is there to take the tank mounting screw. If I can manage to post a photo, I'll post a photo showing the way the engine should look. As I've shown, this engine is seventies production, but yours looks to be "nineties". The original purchaser was lucky to get a runner! Edited By brokenenglish on 04/04/2016 19:36:46 Quote Link to comment Share on other sites More sharing options...
Keith Evans 3 Posted April 4, 2016 Share Posted April 4, 2016 I think it's a D.C. Dart. The screwed hole in the back was for a screw that held the clear plastic tank in place . I believe it's about 0 .5c.c. capacity. Diesel fuel is still available .It's formulation is about equal parts of oil , paraffin and anaethetic ether with a few drops of amyl nitrate . I'm sure I'll be corrected if I'm wrong .! ! Quote Link to comment Share on other sites More sharing options...
brokenenglish Posted April 4, 2016 Share Posted April 4, 2016 Don't bother soaking it in glow fuel. It won't have any effect. I'd use acetone and a toothbrush. Quote Link to comment Share on other sites More sharing options...
PatMc Posted April 4, 2016 Share Posted April 4, 2016 Top row left is a Fox engine, there'll be a number on the side 19, 25 or 35 - all good control line stunt engines in their time. The 35 was a bit of a classic. Dunno what the other two are Centre row left OS Max, again there should be a number another decent C/L stunt engine. Next a PAW probably a 2.5 or if you're lucky it could be an Eiflander Special. Next a DC Spitfire 1cc. Right centre is a Frog 249 BB, it was a fairly "hot" engine in it's time - not sure but this could be a collecters' piece. I'm not sure why BE thinks the the Dart is a late production model, however here are photos of the same engine with tank, a very late version with gold fins & a DC Spitfire from my collection : Quote Link to comment Share on other sites More sharing options...
Former Member Posted April 4, 2016 Share Posted April 4, 2016 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
onetenor Posted April 4, 2016 Share Posted April 4, 2016 Yep a Dart alright .Soak in cellulose thinners easier and cheaper to get than Acetone. Use the rest for thinning dope. I have seen replacement fuel tanks advertised somewhere so a Google may find them Diesel fuel formulations vary so the one mentioned is a possible. I would advise you not to dismantle the engine .Just soak it and turn it over a few times in the thinners .Darts don't like being stripped .. Another thing is you would have to make new paper gaskets for it Take out the carb spray bar and give it a good brushing and use the bristles to clear the hole in the side and the fuel inlet end . Don't try and tighten it too much when replacing ti Quote Link to comment Share on other sites More sharing options...
jeff2wings Posted April 4, 2016 Share Posted April 4, 2016 Top right is a K&B 40 SR pylon/rat racer engine , lower right Elfin 1.5 ? Quote Link to comment Share on other sites More sharing options...
brokenenglish Posted April 4, 2016 Share Posted April 4, 2016 OK, a bit on the other engines. The engine top right looks like a K&B 40 pylon racing engine. The engine bottom right is an Elfin 1.49 with the comp screw missing. Unfortunately, the PAW isn't an Eifflaender Special. Finally, I agree with Tom's comment concerning amyl nitrate BUT, you won't need it if you don't intend to fly the engine. Sports diesels run OK, gently on the bench, on only a 1:1:1 mixture of ether/oil/kerosene. The additive (equivalent commercial additives are available) is only needed when you start asking for serious performance (leaning out and higher rpm, etc.). Quote Link to comment Share on other sites More sharing options...
Paul Jefferies Posted April 4, 2016 Share Posted April 4, 2016 "Don't bother soaking it in glow fuel. It won't have any effect. I'd use acetone and a toothbrush." I would agree with that 100%. Also, It doesn't look authentic but you can make a good replacement tank from the cut down cap off a 1oz bottle of Zap . Paul Quote Link to comment Share on other sites More sharing options...
Stevem3akm Posted April 4, 2016 Share Posted April 4, 2016 Hi, there is a seller on eBay who does repro tanks for Darts and various other engines as well. Regards Steve Quote Link to comment Share on other sites More sharing options...
GONZO Posted April 4, 2016 Share Posted April 4, 2016 Bottom row, second from left is a Cox TD 051(red plastic molding, 049 were black) you can confirm by looking through the exhaust port and you should see a grouve round the piston just down from the piston crown. Third from left is a COX TD 09. The four units on their own to the left are free flight timers for DT and/or motor cut. Quote Link to comment Share on other sites More sharing options...
Former Member Posted April 4, 2016 Share Posted April 4, 2016 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
onetenor Posted April 5, 2016 Share Posted April 5, 2016 Sorry about duplification. RE the spray bar. Depending on wether or not the bar has one or two holes determines how it is replaced in the carb. If only one hole the hole should point downwards.If two holes they should be positioned across the carb i.e. facing fore and aft so the holes a not shown from above.This is important for the running of the engine . If the hole (s) is /are in any other position and it WILL NOT run. This is because of the way the airflow travels through the venturi creating negative pressure which draws the fuel from the spraybar.At least that is the wayI understand it Quote Link to comment Share on other sites More sharing options...
onetenor Posted April 5, 2016 Share Posted April 5, 2016 Pat Mc. I t looks as though you polish your engines.What do you use.? Re fuels and additives they are available on line if you have a good Google. Quote Link to comment Share on other sites More sharing options...
brokenenglish Posted April 5, 2016 Share Posted April 5, 2016 Onetenor, this is getting a bit technical, but I disagree with your statement on spraybar orientation. My reasoning is this: Consider the air flowing through the venturi. The air velocity must be greatest where the venturi section is smallest, i.e. where the spraybar is "fattest", i.e. transversally in relation to the airflow. This "greatest velocity" corresponds to lowest pressure (Bernouilli). Thus, the lowest pressure (greatest suction) occurs at the point on the spraybar that's facing the wall of the venturi ('cos that's where the venturi section is smallest). So if the spraybar only has one hole, it should still be facing transversally in relation to the airflow, i.e. facing the wall of the venturi. I've been setting up all my carbs like that for decades (> 50 years) and it works perfectly. Respectfully, another thing is disagree with is your statement that the engine won't run with the hole(s) in any other position... The real problem, for discussion, is that the hole position(s) are not all that critical. Providing you haven't got a single hole spraybar, with the hole facing back up towards the venturi entry then, in any other position, the carb will work OK. The great advantage with two holes is that, even if the spraybar isn't properly oriented, there will always be at least one hole that "does the job". For confirmation (proof) of the above, you just have to consider the peripheral holes system, used on Cox TDs and Super Tigre G20s, etc. The holes are perpendicular to the airflow, at the narrowest point in the venturi. Edited By brokenenglish on 05/04/2016 07:03:53 Edited By brokenenglish on 05/04/2016 07:27:43 Quote Link to comment Share on other sites More sharing options...
Peter Miller Posted April 5, 2016 Share Posted April 5, 2016 Back when I was using small diesels.Two holes could be located any way round but across the venturi was best. The single hole was always pointed down stream. The intake on your Dart looks as thought there is no bell mouth, just a straight bore. That has to be late as I never saw one like that. The best ones were the Allbpn Darts. Albon was the manufacturer in the early 50s. I had an Allbon Jevelin 1.5 cc engine. That was a real rocket. I could tell an interesting and terrifying story about that engine but I won't. Quote Link to comment Share on other sites More sharing options...
David Davis Posted April 5, 2016 Share Posted April 5, 2016 I hesitate to post this, given the views of such exalted and knowledgeable experts who have already posted, but the engine in the middle of the top row looks remarkably like my OS 40 FP. I believe that they also produced a 35 in the same crankcase. These are superb engines, not very powerful but very reliable and easy to use, very useable today, especially if fitted with a more effective silencer. Just don't expect to get too much for one if you decide to sell it on eBay! Quote Link to comment Share on other sites More sharing options...
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