looking for help with onan lawnmower engine

[ctrhenry]

i have an 18hp performer xsl , no other id on engine , mylar label has faded away
looking for an ignition circuit schematic and some values for troubleshooting the ignition

last owner removed all the wiring in an atempt to rewire the mower, hence my cheap purchase price , it is a twin cylinder vertical shaft,

there is a small gray ring that sits on the crankshaft under the flywheel and it a small black box mounted nearby , a magnetic switch to fire the coil i guess as it has both of its wires hooked to the coil, their is one tag wire off the coil that i dont know where it goes, a condensor off the same coil post [ does it need to mounted to ground to work? their iare also two wires of the stator that go to what i think is a regulator for charging the battery the lead off the regulator is not connected to the battery now though, i think the ignition is self sustaining
and grounded out to shut down the engine, but i can not see the forest for the trees , i have the motor turning over but no spark, any help available would be appreciated