locate the module where the original was.Test spark by removing the spark plug ,insert plug in plug lead and ground spark plug thread on engine cylinder fins and pull starter quite hard.Watch plug gap for spark( make sure plug is good). NOW BE CAREFUL because fuel vapor in the cylinder can ignite put a rag over plug hole.Another common fault with these machines was a leaking cylinder gasket.To test this put soapy water around cylinder base and try to start if bubbles come from around cylinder gasket is leaking and needs to be replaced.Having said all that they were quite a reliable machine even if they were under powered
