Re: 85 Hp Mercury won't shut off....what color and where is the kill wire?
Doess your boat/motor have a Lanyard safety kill switch?
Does this kill the motor when pulled?
If your motor has an ignition switchbox, one of the wires should be Black with a thin Yellow trace line.
This is the 'Ground-to-Kill' wire that runs thru the wiring harness to the ignition switch, where when turned to the 'Off" position is connected to the solid Black Ground wire, killing spark.