Vintage Horticultural and Garden Machinery Club

Thanks Andy, I did not know that. Have never worked on the close cousins of the Mk 25c. Have become a bit anal about magneto ignition. For years I subscribed to a school of thought that if engine had compression, fuel and a spark from a plug resting on ground. It should go. If the spark was blue and fat, as opposed to weak and yellow, all the better. But after reading technical information from Brightsparks, speaking to the owner and trying one of their capacitors. I realized that not only was the plug spark test no real test at all. But how an apparently good magneto could be greatly improved with a top performing condenser, or a modern capacitor. I now have a golden rule that if I cannot get a 6mm air gap spark, I work on the ignition system until I do. The difference in engine starting and tickover between a 4mm air gap and 6mm one is remarkable.