My Onan 2800 Microlight developed a failure to run condition although it would turn over (crank). I tried several things, but since I doubted the plug was firing took it to certified Onan shop. Testing proved no ignition. Disassembly req'd. There is an ignitor module behind the flywheel/timing wheel that is pulled to get to the ignitor module. Replaced that module & its been running good for 10 years & 400 hours.
You may want to find an Onan shop for this one. I was treated very well & they cut me some breaks on the hours charged because it was such a job. The module was only $80.
Let's Roll. !
FMCA SKP GS GPAA NRA USN (Ret)