Re: Johnson 1969 55hp warning horn?
Your motor has a temperature sensor on the top, starboard side of the cylinder head. There is another one on the lower, port side, but that is not for the hot horn.
Look for a tan, 18 gauge wire - that will run through the wiring harness/plug, to the steering position. The remote control unit for your motor is different than the later units, which do have a hot horn in them. You indicator would be mounted on the dash somewhere. Either a horn or warning light would be used. Whichever is the case, the warning device would be wired to a 12VDC source on "the hot side" and to the tan wire on "the ground side."
If your motor were to overheat, the sensor in the head would ground, closing the circuit and sounding the horn or illuminating the light. All you have to do, is to find the tan wire and hook up a light or horn, as described.
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