TDC mystery position??

Just plain weird weird weird. I detail newbies how to find TDC dead on and have done it a lot in past and lately --- till just now on Trixie Combat --- which was timed in 1st kick responsive running --- just no charging --- so found old Peel's single phase alternator and went to put it on --- and knife edge mark 0-TDC and 30' BTDC as factory dial long gone and not trustworthy anyway --- to find a probe on piston places TDC mark on alternator rotor not lined up with center line of barrel but to rear of barrel center line --- in area I'd mark bad alternator 30' bTDC.

I can't deny the piston is at TDC so must assume the proper rotor line is off set by woodruff key 30' retarded. or it it just me?

So is it old news to rest of Nortondoom that the rotor mark does not directly line up with crank throws but is offset for some esoteric reason?

I will know by tonight once contact breakers timed by test light and start and runs nice, then go look and mark what's what for next time's ease.

hobot said:

to find a probe on piston places TDC mark on alternator rotor not lined up with center line of barrel but to rear of barrel center line --- in area I'd mark bad alternator 30' bTDC.

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If you had made the timing marks through the timing aperture in the primary cover then the TDC mark would be approximately 30 degrees away from the barrel centre line-because the timing aperture is positioned to display the timing mark at full advance, and not at TDC.

woodruff key 30' retarded. or it it just me?

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For some reason I'd assumed the cast lines in the rotor would line up with barrel center when crank at TDC. To see TDC when last running right I had to duck down, to see the proper red marked rotor line position with time light and seemed to line up under barrel, while run up showed red rotor landing in view port area dang close
to the 30' bTDC I'd marked by degree wheel.

Will just re-check piston stop to stop 0'-TDC and proceed by manual to get ignition and lift off again. Then maybe I'll remember about where rotor indicator lands in relation to the barrel center line.