So - I changed the fuel filter, started the engine - it idled for five minutes and died. I touched the coil and it wasn't warm. Had trouble starting again, then it started and died. I took the top of the carb off - the bowl was full. I think you're right about this not being a fuel problem. It is a new build. I think the timings right on - it was just checked. I'll check it again. Thanks for the pointer.
