Re: 87 force 85hp ignition switch
At the switch, blue goes to one "M" terminal, white goes to the other "M" terminal. This is the stop circuit. When the switch is off, both "M" terminals are in continuity and the CD box white wire is grounded through the blue wire.
Red connects to "B" terminal, Green connects to "C" terminal and yellow connects to "S" terminal. The "A" terminal is usually labeled "I" for ignition. It should have power only when the switch is in the run position and is used only for things you want powered when the engine is running, like gauges and overheat indicator. If you have a voltmeter, just double check it. It should have 12 volts when the switch is on and 0 volts when the switch is off.
Black and orange do not connect to the switch. One wire from the overheat indicator connects to the "I" ("A"?) terminal and the orange wire connects to the other wire of the indicator. When the engine overheats, the switch on the head closes and voltage can now flow through the overheat indicator.
Black is used as a ground if needed (for gauges etc.)
At the engine terminal board near the starter, you connect the wire cable color to color. Starting from the top, yellow, purple, white, green, orange, red, blue, and black. In order for the engine to stop, blue MUST be jumped to black.
Yellow is the start circuit and only controls the solenoid and starter motor. If the microswitch on the side of the bottom carb is not depressed, the starter will not be energised.--Neutral safety interlock--engine can not be started in gear. Green is the choke circuit--pushing in on the key while in start or run position will energise the choke. Orange is the overheat circuit. Red is the battery and will have two wires attached to the engine wire loom cable--one comes from the rectifier and the other comes from the circuit breaker. This only charges the battery and supplies power to the ignition switch in this engine. Purple is one half of the AC voltage from the alternator and is used as a signal for the tachometer--so under the dash it connects to the "S" or "sig" post on the tach. You must use a special 20 pole alternator tach with this engine.
The alternator has separate windings for charging the CD boxes and as long as the flywheel is turning, it delivers power to the boxes. With this type ignition, it is self energising and you must do something to stop the engine. That something is to short the CD box white wire to ground. This is done through the switch--"M" terminals.
So, now that you know what the engine circuits are, you can wire it and trouble-shoot. If you are not getting spark, the most likely culprit would be an incorrectly wired white wire. I noticed that you have multiple white wires under the dash. Be sure that only the white from the cable is connected to the "M" terminal.
