Yes, the tiller electric/standard set up does not use a solenoid. The positive cables are heavy enough, and short enough to handle the draw of the starter motor….
This is not the case for a remote electric set up though. The length of the hot wire running up to the key switch, then running back to the starter, would be too long to effectively carry the current needed by the starter….The key switch is not designed to handled that current load either.
The remote electric kits for these engines included a junction box with a solenoid, similar to what the older large engines used. This set up could be eliminated if there was some place to put a solenoid on these engines, but we know there is no room to spare on these engines. In later years prior to 1993, there was a specific remote electric engine built that did not use a junction box…There was no recoil starter on these engines, and the solenoid was mounted where the recoil used to be…
OK, so the picture shows the junction box end of the engine wiring harness. So, that black wire can be the battery negative cable that is fastened to the terminal board in the junction box…Another black cable is run from this terminal to the battery, and a smaller black lead runs from this terminal up to the key switch for the stop circuit. So, it is very possible that the blue/green/whatever color it is lead is just a spare that is not used. Perhaps OMC used some old stock harness from another engine for this kit, and just capped off the unused lead.
In any event, you could convert this to use a red plug set up, but where in the engine would you mount a solenoid? So, I’m guessing you do not have the junction box for this set up, or the boat end of the wiring harness. Do you have any old style PTT boxes that included a solenoid? If so, it might be easiest to just use an old remote electric control box, cut off the big red plug, and hard wire the leads using the terminal board and solenoid in the box. You may want to add the 20 amp fuse to the red lead running up to the key switch from the terminal box….
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