Re: johnson 50 hp hydro electric problems Please HELP
OK, so its a 60hp Johnson that you have, not a Chrysler.
The control box for your 60hp Johnson probably has a black plug. Generally speaking, it is not compatible with your 1972, 50hp motor. That is not to say that most of the circuits will not perform the same functions, but there are differences. Exactly what those are, I'm not sure, because I don't have a service manual for the 60hp motor. As much as I hate Clymer and Seloc manuals, one good thing about them, is that they tend to have a lot of wiring diagrams in them. Perhaps you can find one for the 60hp and one for the 50hp, so that you can compare them.
One difference that I'm reasonably sure of, is that the 60hp motor did not come with a control box that has a neutral safety switch for the starter. Your 1972 50hp does and the reason why you had problems engaging the starter solenoid was most likely because that switch was defective. Since the later box doesn't (I think) have the feature, that problem is not an issue at this point.
I don't think, however, that the wire color will be any different between the two control boxes. OMC used white wiring for its starter circuits pretty consistently, so I think yours will be white, regardless of whether there is a neutral safety switch in the circuit.
As for the black/yellow wire, the fact that you don't have it connected to anything, is why your motor won't shut down when you turn the key off. That circuit is a ground for the powerpack - when the key is in the run position, the ground circuit is open and when when it is in the off position, the circuit is closed, grounding the powerpack. The black/yellow circuit should be connected to the "M" terminal on the key switch.
I'd love to hear from F R on this issue, because he knows the older OMC motors very well, but I am going to guess that the reason why the 60hp control box doesn't have a black/yellow wire to match up, is because it has a different ignition system. That motor uses points, a distributor, an amplifier and a single ignition coil, to provide ignition. Electrically speaking, I'm not sure how that motor shuts down, but its apparently not via a black/yellow grounding circuit.
Try connecting the black/yellow circuit to the "M" terminal on the key switch and see if that solves your shutdown problem.
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