My problem is the wiring. When I took the ON and OFF switch wire off the magneto I would get a spark. When it was on I wouldn't. So what can I do to fix that. Is it just replacing the wires or what. Thanks.

When that wire shorts to ground, it kills engine. When you turn on switch, you are making a connection. You may need a new switch, a single pole doublethrow switch, and only use 2 connections, or turn that one upside down.