I usually install the o-ring plugs and then epoxy. I test for leaks, then I'm good to go. Never had a leak either, but only time will tell. Actually... what amount of time is acceptable to have a carb rebuilt again? 5 years? 10? 15? Or is it mileage dependent? Or just when it starts giving grief? It's a never ending cycle. At one point or another, a carb will always need rebuilt.Just putting epoxy over the plugs is a temp fix. To fix leaky Qjet plugs right, you have to drill the bad ones out, then tap the bosses for screw in plugs which you coat the threads with epoxy.