I have got the machine back together, having rebuilt the blades. I started it today, for the first time; it was a bit hard to start, and would initially only run on part choke. Eventually it would run on throttle only, but at pretty well full revs only. It all suggested the need for a carby tune up to me. Can you help please Bruce, either with instructions, or a link. The engine again is B&S 130902 1260 01, vertical shaft with tank mounted carb.Many thanks.