Re: carb rebuild
Sounds like idle jet plugs. Different sizes are for different runs of the carbs, just discard the size that does not fit your carb. No, it's not absolutely necessary to replace the original plug, unless the original plug is leaking. This plug must be inserted convex side up (crown up) and then flattened with a flat faced punch to effect an air tight seal. You can remove the idle mixture screw, good time to inspect the packing washers too, and spray into the needle seat with carb cleaner.<br /><br />It's important to soak and /or spray carb internals with carb spray, followed with compressed air. Replace float needle valve, adjust float as needed and replace gaskets etc. Make basic needle adjustments for low and high speed settings and you should be good to go.
