[john walker's workshop]

a common problem, requiring more effort than you thought occasionally. 1st, get your 16mm socket and grind down the leading edge to get rid of the bevel, so you can contact the full surfaces of the hex head on the plug. firm pressure without jerking is your only hope. if it still strips, it's chisel time. you have to get a bite in the brass ring, around the hex, with a small flat tipped chisel and see if you can rotate it without going thru into the carb body. the hex cap can actually be chiseled off because it's hollow, to give you more working room. if it still doesn't budge, a few notchs can be cut with a piece of hacksaw blade thru the brass, but not thru the aluminum sealing ring below it. then the chisel can be applied again. the notching tends to relax the grip of the plug, and they usually turn after you do that. JUST BE CAREFUL NOT TO DAMAGE THE CARB BODY UNDER THE PLUG! if you do, a machine shop can spot face them, so all is not lost.