Yesterday we had a old (say 1150hr TT slick- I only log engine airtime) which I sent in to Aero Enterprizes with the idea to keep as spare (notice the Swiss on Falke had musical magnetos). Steve when he opened it up said is was one of the worst he has seen even though his ogranization did 500hly on it about 450hrs ago. The trouble is the coil has been getting too hot and was failing under heat gun and Steve then suggested to look again at the installation and consider a small jet of air directed to Mag. Mag is now only core exchange value.
The h36 then had the L2000 but now it has S2500. I have already made up aluminium tube to direct air onto the mag hidden down the back. In many aviation installations it is the norm to direct a jet of cool air onto the magnetos and I would consider it a good idea for Dimona especially in AUS. Have a look at a few GA planes. I do know Jabiru require a jet of air and or heat shield at their coil and the Powermate regulator in some installs needs a jet of air onto cooling fins. Electronics/electrical hate excessive heat My interpreting mags is they last the life of the aircraft which in Lycoming would be 1800 to 2100hours but in the case of Limbach it is 1000hrs. As one LAME friend told me as he services a Mag you can tell when they are too old - it shows just like looking at a horses mouth. Personally I would consider (need to pass it by John V) if you keep a log book with a magneto (the Swiss do!!!) then it could be serviced and be used in multiple aircraft. My friend who was chief engineer with King Island Airlines said they would do musical magnetos on Chieftains and would would change a magneto while the passengers sat in terminal for 1 hour. I seem to remember a very small card similar to a parachute repack card was with each magneto which was the mag log book. Anyhow my bottom line is consider air onto magneto like most GA do and maybe even consider doing services say 400hrs as we only have one magneto - it is cheap insurance and the Germans ONLY call for 250hrs on Slick. Ian M
