Scintilla lever will interchange with the Phelon magneto. I don’t have part numbers. The flywheel and point cam from the 7.5 hp motor won’t interchange because the crankshaft is smaller on the Mark7 & KE4 . Are you sure you have the cam for the 10hp. motor? Does it fit on the crankshaft? On this type on ignition, when moving the magneto lever, your advancing or retarding the timing, so there is no correct timing. You will also need a different flywheel key than the one from the Scintilla. It would be a good idea to change the crankshaft seals and remove the fuel filter to check its condition, if it is still in there.
That may be in need of clarification…
While the mag lever does in fact change the timing…I do know there is a timing process involving a ring and a pointer for use with these Mercs. It would be similar to the pointer used by OMC… That ring and pointer certainly helps set both cylinders to fire 180 degrees apart, and it may in fact also set the points to fire at the correct piston to TDC relationship..
I have NEVER used one but know of them, J. MacIntosh ,(spelling?) probably has them…
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