As the others say, its just a case of keep unscrewing the nut until the
flywheel comes off. When you start, the nut will loosen and then tighten
again as the nut binds on the flyhweel, keep loosening (when you might have
to tap the spanner with a mallet) and the nut will draw the whole flywheel
off the shaft. Have a couple of bits of iron handy to place accross the
magnets as keepers. I am told that this flywheel is self keeping but others
say it is not, to be sure I always stick a couple of bits of metal accross
Once the flywheel is off it is usually 2 slot headed screws in the centre of
the backplate that holds the whole assembly onto the engine. Undo these and
the whole magneto should come off the engine.
The next bit is coil/condenser testing to see if it will work !! There are
some very good articles in the Stationary Engine magazine that covers the
rebuilding of these magnetos however I don't have my copies handy to advise
issue numbers, perhaps someone else can advise ?
Stationary Engines Scotland
Click to see the full signature.