Problem solved. The clip on the plastic box where the wiring from the pulse generator meets the loom was broken allowing the two parts to vibrate apart thu8s giving a flickering neutral light and no sparks. Hurray!!! A small zip tie was used to hold the box together, all I need to do now is put all the plastics back on. Out of interest, will running on the street with no thermostat cause any problems, ie not allowing the engine to reach full working temp causing it to seize?
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