onan 18 hp wasted spark ignition

[keith oh]

No spark

 

[motoman]

Ya gotta go much further to get help here unless you are joking. Wasted plea.

 

[reynoldston]

No spark? Spark plug, spark plug wire, coil, flywheel, points and condenser (older engine), module, Some engines have a coil that run off a battery so it all depends on what you have. motorman is right we need more to go on.