Hi Grumpy, Have just had a play with generator and it started 4 times, cut out and started first pull each time. Did check for spark by holding spark plug near to valve cover and pulling over motor, had good spark. I guess what is happening is the spark is dying or going somewhere else, am i on the right track? What exactly is a in-line spark tester and can i make one with shed equipment or will i have to buy one.