Working on an M that I recently bought. Seemed kinda hard to start (it would start and run) so was checking things out and discovered I couldn't get the magneto to trip while trying to time it. I'm familiar with the procedure, #1 at TDC (pulley at first mark), move mag away from engine block until impulse trips. So I figure magneto must be a tooth or two off. After a couple tries, I've got it reset, now the mag trips at #1 TDC but it is at the limit of the adjustment. The mag is at the end of its adjustment closest to the engine block. All my other letter series tractors seem to time correctly with the mag somewhere in the middle of the adjustment. So, the question is, do some mags time at the adjustment limits or am I still a tooth off on the gear?