Vekenti 1 #1 Posted October 10, 2020 (edited) Hello, I recently acquired 2 O&R 23s for a very good deal. I've been flying glow engines in my planes for about a year and a half now, but wanted to get into gas and these little engines seemed like a great start. If I get them running good I might even put them into my RC DC-3 :). I already have both engines taken apart and the internals are quite clean. Pleasantly surprised for engines that can be as old or older than myself. I'm going to mount a carb on both to convert them to R/C. I'm not really sure on how these engines really work, specifically the spark/ignition part. I know back in their days there were ignition coils to produce the spark. Those small coils seem few and far between now so I have been trying to find alternatives. Has anyone used CDI on these old sparkies? I have bought an used CDI unit to test it out. What else can I use to run ignition with these engines? Any help would be appreciated, Noah. Edited October 10, 2020 by Vekenti Pictures 1 factory reacted to this Share this post Link to post Share on other sites
factory 487 #2 Posted October 11, 2020 I've got a few of the O&R model plane engines in my collection but haven't tried to run any of them, none of them had a coil with them but modern small ignition coils are still made, here is one I found with a quick search; http://www.springmillsmfg.com/model-airplaine-ignition-coils.html The coils would have been used with the points in the engine, capacitor across the points and a low voltage battery pack. Later on O&R started offering glow plugs for these to compete with other manufacturers, this was a big mistake as they tended to run too hot causing the alloy con-rod to fail, they later used a steel con-rod which resulted in the cylinder heads being blown off. This gave the O&R model engines a very bad reputation, they eventually they stopped making them and went into producing the larger Compact Industrial engines from the 1960's onwards. David Share this post Link to post Share on other sites