The little O&R 23 glow was a jewel in those times, for sure! I remember the instructions said to break it in very rich, get it started, richen it, and then remove the battery from the glow plug. With all my 8th grade wisdom, I said to myself "it'll stop as soon as I pull the battery, like my ignition K&Bs do". But I marvelled that it kept plugging along, blowing smoke and castor all over me. The ignition K&Bs didn't have the compression or the metallurgy to handle glow very well, even with the higher compression heads they sold. Like you, I could put in half a dozen flights (U/Control) with the O&R with no problems whatsoever. Fun days for sure!

Clair