What is it? Speed plane or something else...

getback wrote:Coming right along Bob , i didn't know the older Atwoods, ect. needed more castor , Thanks Ken ! i will have to mix something special for the next try out . This Fall!!

If I'm reading Ken right, more castor is not going to help any engine to start quicker or run better, just help it from wearing out sooner??????????

I feel like this one will run if I find the right combination of fuel, glow plug and amperage.

Testing some plugs visually outside the engine I find that while 2 amps on some will give a nice bright glow while others take 3 amps to produce the same result. So much for me always adjusting amperage to fall into the green zone just below 3 amps.

Checking one of those cheap Taiwan $15 for 10 plugs I found it's happy at 2 amps. No wonder I burned the first one I tried out when I cranked the meter up to 3 amps.

Read what's posted and believe what you experience. For instance, I run Fox .35's and when I say run them I mean probably like no else does. So everyone who runs a Fox will tell you it will overheat if you don't use at least 29% castor oil. Now when Duke had those instructions written, it was 1948. Duke then started to use synthetics in the 70's, the engines took a complete dump due to the low cost synthetics he was offering. The instructions never changed. George Aldrich however worked for Duke for a short time and he always felt that the high percentages of castor were problematic. These engines would  varnish up and then they coke up with carbon. So if you don't manually remove the carbon, yes it can harm the engine rather then do it good. George Aldrich then made GMA ( His initials ) 50/50 22% oil fuel. I've been running this piston and crankshaft destroying fuel for 21 years now and never had a failure related to oil.  So the naysayers will still tell me that my engine will self destruct and ruin do to overheating because the castor takes the heat away. Well I'm tired of explaining it won't.

                 Back to the Spitfire, the fits of these engines are quite crude compared to a modern engine. The higher percentage oil cushions the poor tolerances such as the rod and wrist pin fits, but it also increases the compression when starting the engine. The engine will also hot start a lot better equally due to the higher oil due to the cylinder expansion. The Spitfire will also run better on high nitro as much as 25% but I would try and use 10%-15% nitro initially. Many of those older engines use short plugs as well so be on the look out that a long fits without striking the crown of the piston. You did mention a Enya #3. That is a hot plug which is good ( Expensive) but good. A Thunderbolt is one of my favorites, the K&B 1L is also a good choice. If you only have Cox fuel which is 25%-35% nitro, the Enya #3 is too hot and will cause pre-ignition prior to it running and could even damage the engine. Hot plug/lower nitro, higher nitro/ colder temp plug.

Thanks Ken, That's what I was thinking, more castor resulting in higher compression being the only benefit in a prime only start to run. But compression doesn't seem to be a problem with this engine.

The glow plug thing. I tried three altogether. Mostly medium lengths. All initially did not interfere with the piston, but one after a few flips and with the glow plug heating up caused expansion and the piston hit the plug and would not complete the cycle.

I'm thinking about mixing 1/3 Cox 35% with 2/3 Traxxas and some added castor just to see what I would get. Might also hitch up a tank just for grins. But, I have never seen an engine so far that would not at least run a second or two off prime.

". . . K&B 1L is also a good choice" I believe Ken meant a K&B 1S plug for the Spitfire (short as opposed to long)

ticomareado wrote:Bob, I PM'ed you yesterday on an interesting Enya matter.

What tico……….was pointing me to.

Hersheys  to a chocolate lover.

.29 always a favorite of mine and with an early plug too.



Early Enya .09 Model 3001 with early plug.  Replaces one I gave away last week.  



and an also ran off the shelf model .19 R/C



All three less than ten bucks apiece shipping and tax included. Look Ma, no drive washer tool marks.

Thanks Victor.  Not the first one here to give me a heads-up on these specials.

So would you consider giving me a bird dogger's deal on the .09 ?

ticomareado wrote:So would you consider giving me a bird dogger's deal on the .09 ?

Nope, but you get my eternal thanks and admiration for free.