Carb Cleaning/ proper sizing of jets

All you guys cleaning your own carburetors and wanting to make sure your pilot jets are sized correctly, here are the drill sizes with the corresponding jet size. Remember, even though you can see "daylight" through a jet, it does not mean its CLEAN!!!!! You can purchase a numbered drill index with sizes 61-80. The first number is the drill number, the second is the corresponding jet size........80-33,79-35,78-40,77-45,76-50,75-53,74-56. I hope this helps.

I use a torch and hemostats...I dont know how comfortable I'd feel running a drill bit through my brass, seriously, all it takes is a hairline scrape and the jettings off...a torch melts any oil residue very quickly

I use a torch and hemostats...I dont know how comfortable I'd feel running a drill bit through my brass, seriously, all it takes is a hairline scrape and the jettings off...a torch melts any oil residue very quickly

a torch works very well along with the yamaha carb cleaner. That stuff really works when heated. If you use the proper size jet drill, you will not be removing any material. Like they say " there's more than one way to skin a cat" I just prefer the jet drills only on the really nasty carburetors. The best would be to just replace the jet, but sometimes that isn't an option. Besides, lets say you have a pilot jet plugged solid, once you use your torch and look through it and it seems clear, How do you really know its the proper size. With a jet drill you will know.

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