I removed the brass plugs from my 3010 Mule's carburetor and had an issue with one of the screws galling. I also committed the sin of letting my drill bit kiss the top of the screw so you know the rest. I unscrewed it several turns before the slot became unusable and I had to get the assistance of a machinist friend to drill it out. The screw came out ok but you can see where some of the threads were damaged and he did not possess the proper tap to chase them out.
I will have to purchase two new screws but I really need to clean the threads up first before I get another mixture screw fastened in the bore due to bad threads. He suggested that if I could not secure a tap to try and buy a screw that is long enough so I could screw it in little by little and tap it to straighten the threads and also cut a small "V" on the starting threads to act as a cutting tool. My friend guessed the threads were 6mm x 0.5 but did not have the correct thread guage to verify with. Does anyone know for sure if this is correct?
All suggestions welcomed.