C-Fast idle problems

Well, we've got our new to us C, running. It was sitting for about 5 years so, we cleaned off the crud, flushed the tank, had carb rebuilt, new plugs (D-21 I believe), cleaned and gapped points, checked valve adjustment (0.018 cold), confirmed mag timing to be correct, cleaned pan, new oil and filter and started it up. It won't settle down to low idle on the governor so it idles pretty high on its own, but it's smooth and with some help on the carb linkage, will run quite smoothly down low. The linkage is terrible sloppy and needs a rebuild to refresh the bushings and bearings on the shafts at the very least. The whole tractor needs a rebuild, which is intended, but there's no time now. Problem is, when the throttle is opened wide it starts missing. It sounds like the plugs are breaking down, but since they're all new I find that hard to believe. What I haven't done is change the wires, but I think I will, from a good machine, to confirm they're not the problem. Is it possible the mag is the problem? This is the first mag machine we have. Cap, rotor and points look good. Maybe a new condensor or coil? Thanks for the past help. The heli-coil for the pan worked great, and we just used the new 7# rad cap we had. Presently the seat pivot, shock and spring are being renewed, because it was dangerously sloppy.

Well, I think you may be on to something with your plug wires. In a direction at least. And yes, if the distrubutor cap on your mag is bad, it can have the same results. While you're there, don't forget points and condensor.

Just for S+G, are you quite sure that it isn't running lean?

Good luck, Andy

The points are maybe pitted & dirty & don't make good contact at high speed. If it starts I would say the coil & condenser are ok.