OUCH...Doing that to a MSC prop is gonna leave your hand not feeling well at all....I hope your OK

Guys, I just talked to whaturi (him and I fly a lot together and I sold him that engine) What happened is the high speed needle backed out causing it to go rich. This is one of the Brison's Gary did and used the lightened pump spring on it so the needles only need to be no more than one turn open. His was out 1 3/4 turn but replacing the plug is not a bad idea anyway.

This Brison has been rock solid as most Brison's are

I suggested he strecth the spring and at the same time take is dremel to cut grooves on the part of the spring where it contacts the carb body and the needle so it will not back out again. I've done this with loose 3W needles and it works well as it acts like a lock washer and "grabs" the carb and needle