I turned the poppet valve from a to b then c on a VSX160 and got no RPM change - unloaded - no idea what happens under load. From memory, my FC Commando doesnt have the ABC markings, just the black poppet - not sure about yours MF.
MF, The coil was really rusty muck on the poles - a bit of sanding on it and the flywheel, and I had spark again. Same on an old Briggs (1993 classic 35), spark instantly vanished, remove coil, clean rust, and back to bright blue.
Now I think I am going to have to go outside now and jump start the car - I accidentally left the door slightly ajar (first latch) overnight. Bugger.
