This is an upcycling, save the world, reuse project. The plan was to save a mechanically good outboard engine with a aging failing electromechanical ignition system, with an inexpensive salvaged modern system from a automobile.
Please refer to the attached word document in the files section.
it seems that decreasing fluid viscosity lead to more predictable operation of the transmission. however fluctuating servo position (verified by unplugging the servo in neutral position) leads me to believe that either the 7805 voltage regulator needs more or total isolation from the noisy 12v boat motor electrical system.
this i never bargained for. the transmission (forward neutral reverse) is a electrically contolled hydraulic unit that has been giving me no end of grief. originally controlled by a pair if solenoids moving a hydraulic spool valve deep in the leg of the motor, multiple dissassembly procedures and bench testing resulted in the replacement of the solenoid with pushbuttons, an arduino, and a servo. now servo noise and some question regarding hydraulic pressure differences caused by various in fluid viscosity have been hampering a honest effort of tuning the ignition system effectively.
i have been experimenting with arduino timing contol, but opted for a ready made megajolt solution for this project. it can be controlled using "mechanical advance" algorithms based on rpm, manifold vacuum, or throttle position. I am currently using rpm based advance, but believe tps advance will be the better overall solution to cure hard starting where there is not enough advance.
Some autocad drawings of brackets and pickup wheels were created and cut by a local water jet cutting company. I have found the reluctor pickups to be very reliable and will pick up metal ranging from 1/16 of an inch thick on up. My smallest pickup disk to date is this one, about 4" diameter with 1/4" notches.
The biggest epiphany moment for this project occured when realizing that a wasted spark 6 cylinder ford EDIS ignition module would be ideal for timing a three cylinder two stroke motor. By eliminaing half the coils abd using every spark (including those from a 6 cylinders wasted exhaust cycle) expensive antiquated ignition parts could be abandoned in favour of a modern inexpensive auto wrecker solution.