I am not sure if this is the right place to ask this:
I have a ED BEE MK1 that i want to use in a 1/2A controline all sheet plane. This engine runs but it has hard starting( i used an electric starter). i am concerned that having a screw-in backplate which also accepts the intake tube, there is a possibiity of the intake timing being changed from dis-assembly. Does anybody happen to know the intake timing specs? I read the BEE MK 2 has increased power due to a longer intake period. Is there an advantage to utilising this period on the MK1?
Looking forward to any advice.
Well apart from sharing the name there is not a lot in common between the Mk1 and Mk2 ED Bees-porting is quite different-virtually everything is different-except probably the disc-which seems to be the same in both-so forget that aspect of the timing. Mk1 Bees did not wear well-so if it is hard to start you're pretty much stuck with it. Take note of the warnings regarding electric starters-though the Bee is a lot more solid than many other small diesels.....steel conrod for a start....which means that if you get it badly wrong you're likely to break the gudgeon or crankpin rather than bend the rod as usually happens. Personally you could hardly have picked a worse offering to power a CL model with-they were pretty gutless (so were the Mk2s-until the very last model variant!)-about the same power as a DC Merlin of 3/4 the size. That being said you can still use it for your stated purpose-but you'll have to a) keep the model light, and b) possibly fly on shorter lines than is comfortable. In any case Footloose has made you an extraordinarily generous offer-in your position I'd accept it gratefully. Now it is possible to misassemble the Mk1 ED Bee (and the 1.5cc Hornet) and mess up the induction timing-this occurs when the backplate is screwed home after being removed-or even just partially undone-and the crankpin seats in the induction slot (which is bean shaped-and on exactly the same radius from the central pivot pin as the drive hole in the disc)-this is readily detected though by removing the induction tube-and if the engine is mistimed the rod and bigend will be visible in the induction cutout. This is one of the foible of the Mk1-and there's not a lot you can do about it, except keeping on unscrewing and re-screwing in the backplate until the crankpin seats in the correct hole in the disc.
The Mk1 Bee should turn a 7x6 OK for C/L use-though a 7x5 would be a lighter load-and allow it to get closer to its peak. For FF (which is probably the use it is better suited for) an 8x3 or 8x4 is about right. Bill Dennis has raised some issues about starter fluid that are quite valid-there are many brands-and many formulations-all of them to my knowledge contain SOME ether-but 'some' can be as little as 20%-which makes them totally useless for a source of ether for diesel fuel. The best ones are 80% or more ether-and even here you need to factor in the other components as part of your fuel mix ie-the '20% not ether' is factored into your final fuel mixture as part of the kerosene component so you end up with the appropriate mixing ratios to give at least 30% ether in your final fuel mixture. Experience also indicates that the highest ether blend starter fluids are used in cold climate areas-and those for use in tropical areas are at the low end of the scale 20-25% ether content.....so given where you are -i'd be reading the contents label or spec sheet very carefully to ensure I wasn't purchasing a useless (for your purposes) product.
PS and before you ask-there is NO alternative to diethyl ether for this purpose-there is no other chemical compound that can be used as a substitute.