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I've been through this before, but not with the starting engine apart, once you have the engine aligned internally, the Caterpilar Operation and Maintenance Instructions ( form 10481-6 ) for the D-7 7M,& 3T diesel tractors but both fail to ID #1 cylinder which is closest to the main engines radiator. If you pull the starting engine flywheel cover off and reveal the pony flywheel, there is a mark on the flywheel, could say mag or M with a line under it or just be a horizontal line like mine. There is also a mark behind the flywheel cover on the housing, that should align with the flywheel mark when #1 is supposed to fire. You can put a cork in the spark plug hole and it should pop as you are doing this step, and be 25 degrees ahead of top dead center which is the correct firing point. Now once you figure that out, the next pain in the arse is to get that mag mounted and set to fire a spark in the right order 1-2. If you spin the mag by hand you will notice that it's spring loaded, with weights and the tension increases before it releases and fires a spark, then releases to repeat the same thing for the next cylinder. I had to spin mine by hand, feel the jolt and set it so it would fire the spark, then align the coupler slot with the engine as you mount it, so that this sequence is aligned for #1 to hit 25 deg ahead of top dead center at the same time that mag wants to fire a spark. It seemed that sometimes the slot/coupler would be off and you would have to turn the magneto to mount it and that would move the piston beyond the spot you want it when the mag wants to fire a spark, so I recall. This thing stumped me for days, until I hand set that magneto just advancing to spark, also had #1 piston set to advance to 25 degrees ahead of top dead center which occurs when the flywheel mark aligns with the the mark in the housing. The last thing was the magneto coupler alignment allowing the mag to be mounted and be advancing to spark, when that reaches the correct point. Finally it fired in order and I felt as if I conquered a formidable opponent ! The smoke was unreal, was burnin some oil, shut er down, my other one I can use a handcrank to start the pony and it runs nice. Funny how the book does not tell you which piston is #1, however when the timing marks as mentioned above, align, only #1 should be pushing air/popping a cork out, probably the only way to identify which on is #1, which is on the left as you look at the motor standing on the track. My newer Wico was rebuilt and I think it needed to be timed itself, but I could never get it to time right to the motor, as explained above. I went and found an Eisemann in a box of pony parts given to me, and it was hot, so I mounted that one, did the above and it fired off. The mag must be in time by itself, still have that Wico and will figure out what the deal is someday. This particular manual shows an Eisemann with timing marks to align, one the coupling and one on the housing, ( back end that mounts to the starting engine ). The rotor postion appears to be at the 2:00 o'clock position and the points should be just beginning to open, (all according to the manual, page 71-72) You can also check your point contacts, should be .020 inch gap when the cam is at it's highest elevation.
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