ORIGINAL: GravityTester
I have a Fuji 43cc with a magneto ignition system. I bought it mounted on a plane at an auction so I have no idea of when it last ran. I have tried all of the traditional starting sequences with no luck. After many attempts I got it to run for about 10 seconds one time but most of the time I can't even get it to fire. I put a brand new spark plug in and tested the spark several times. I have even tried spraying starting fluid in the carb and got nothing. I would think that even if I wasn't getting fuel into the carb it would ignite the starting fluid. I'm out of ideas so any suggestions would be greatly appreciated.
I'm personally very fond of magneto ignition. They are pretty simple devices actually. Points, condenser, coil, plug. You might check your spark timing, make sure your point faces are clean and properly gapped, condensers seldom go bad. You can check your coil windings with an ohm meter to make sure you are getting a resistance reading. If you get an infinite reading you have open coil windings and your coil need to be replaced. I think you indicated that you are getting a consistant blue/white spark across the plug gap. If so your coil, condenser and points are probably OK. That leaves ignition timing.
Bill