1962 75hp Johnson Super SeaHorse Ignition Help

[gossamer7]

I was wondering if anyone had a schematic for the colors and configuration of the magneto key switch for the 1962 Johnson motor. The service manual that I found on the 50's to 70's Johnson motors didn't list mine and the colors aren't all the same. I have a small white wire which I traced to the starter solenoid and have hooked up to S, a large red wire that goes to A, a small black wire that goes to one side of M and a gray wire that goes to the other side of M and a large dark green wire that goes to B. The motor sounded like it wanted to fire over for a few seconds but then when I cranked it more the starter motor sounded like the only thing running. I checked the solenoid and am still getting spark, so I' wondering if something in the switch is wrong.

 

[MCM]

Re: 1962 75hp Johnson Super SeaHorse Ignition Help

The white wire would go to a neutral start switch in the control then to S, the gray is usually reserved for the tach and wouldn't connect to the switch, the red would go to B, the black would be ground and connect to the M next to the A, and the green would probably connnect to the other M, the A is for accesories such aas any lights, horn, etc you want to run off the switch.<br /><br />I wont swear to it in court, but I'm pretty sure. Its the same switch as in my manual, the only thing different is the green wire, mines yellow and black, which is the kill wire. EDIT: Also any accessories you run off the switch will need to connect to the ground on the switch

 

[MCM]

Re: 1962 75hp Johnson Super SeaHorse Ignition Help

If you have any doubts you should get an OEM service manual for this motor, it has wiring schematic in it. Ebay is probably the cheapest place to find one.<br /><br />Good Luck & hope that helps

 

[Joe Reeves]

Re: 1962 75hp Johnson Super SeaHorse Ignition Help

Is that 1962 75hp model a electric shift unit or mechanical shift?<br /><br />Is the ignition the automotive type or magneto?<br /><br />Both of the above makes a difference in the switch wiring.

 

[gossamer7]

Re: 1962 75hp Johnson Super SeaHorse Ignition Help

The shift is a mechanical shift and I believe that it is a magneto ignition but I'm not sure. The underneath of the flywheel looks like an alternator and it has a coil and a distributor. I'm not completely clear on what a magneto system is. There are 5 wires coming through the factory harness that would indicate a magneto switch, but the original switch he gave me only had three posts. He also included an ammeter gauge if that helps.

 

[gossamer7]

Re: 1962 75hp Johnson Super SeaHorse Ignition Help

I just looked at his description on the shifter and it is listed as an electromatic shifter.

 

[Joe Reeves]

Re: 1962 75hp Johnson Super SeaHorse Ignition Help

If the engine is a mechanical shift model, there will be a shift lever on the starboard side.<br /><br />A V4 magneto will have the spark plugs wires leading straight down out of the bottom of the magneto distributor.<br /><br />A V4 automotive distributor will have the spark plug wires leading from the top sides of the distributor. This type ignition will also have a automotive type ignition coil in plain sight.<br /><br />Now, with the above info, what type shift and ignition system does that engine have?<br /><br />That three (3) post switch.... don't hook anything up to it just yet.

 

[gossamer7]

Re: 1962 75hp Johnson Super SeaHorse Ignition Help

It has an automotive type ignition and a mechanical shifter.

 

[Joe Reeves]

Re: 1962 75hp Johnson Super SeaHorse Ignition Help

The three (3) terminal ignition switch would be proper with the engine as you describe it.<br /><br />If there is a large component under the flywheel with quite a number of coils, that would be an alternator, in which case there should be a junction box with a voltage regulator, starter solenoid, diodes, etc etc within it.<br /><br />The large "Green" wire would attach to the BAT side of a amp meter.<br /><br />A "Fused Brown" wire would connect to the GEN side of the amp meter and the other end of that fused wire would attach to the BAT terminal of the ignition switch.<br /><br />There should also be a large "Brown" wire that would lead from the GEN side of the amp meter to the fuse which is attached to the diode assy.<br /><br />The "White" wire attaches to the "S" terminal of the ignition switch.<br /><br />The "Red"" wire attaches to the "I" terminal of the ignition switch.<br /><br />There should also be other red wires that lead from that "I" terminal that would supply power to the "Ignition On Light", the "Temperture Warning Light", and the "Choke Switch", along with a "White wire that has a Red Stripe" which is a resistor wire that leads to the + side of the ignition coil.<br /><br />A "Tan" wire should be attached to the other connector of the Temperture waring light. That "Tan" wire would lead to the heat sensor on the engine's cylinder head.<br /><br />The "Black" wire attaches to the ground side of the "Ignition On" light.<br /><br />The "Gray" wire would attach to a tachometer sensor terminal if one was installed. If no tach exists, insulate that wire and do not attach it to anything.

 

[MCM]

Re: 1962 75hp Johnson Super SeaHorse Ignition Help

Thanks Joe, Gossamer, sorry about any bad info I gave, I didn't see any brown or tan wires or "I" terminals in orig. desc. <br /><br />I did provide a disclaimer though

 

[gossamer7]

Re: 1962 75hp Johnson Super SeaHorse Ignition Help

Thanks guys. I appreciate all of the useful info.

 

[Joe Reeves]

Re: 1962 75hp Johnson Super SeaHorse Ignition Help

MCM.... No bad info on your part. Gossamer didn't list those wires, I simply added and inserted the wiring that should be there.

 

[Joe Reeves]

Re: 1962 75hp Johnson Super SeaHorse Ignition Help

You stated:<br /><br />I switched the ignition to the switch and colors listed in the previous topic and now the starter is the only thing that cranks. The motor doesn't fire up and shut down like it used to. There isn't a white with a red stripe for the + side of the ignition coil but I traced the grey to the + side, which I have hooked up to the I terminal. The only wires left coming through the factory harness are a tan and black wire. Is there anything else I can do to get the motor to fire over or could there be something else wrong. The previous owner claims that the motor was in perfect working order and recently tuned up by Johnson( who he works for). <br /><br />---------------------------<br /><br />I Replied:<br /><br />Apparently someone has changed the wiring to suit themselves rather than keeping to the factory specifications.<br /><br />All I can suggest is to trace the wires of the wiring harness at the ignition switch end to whatever they're connected to at the engine, then wire the ignition switch as needed.<br /><br />The ignition switch terminals are:<br /><br />Terminal "B" - Whatever wire is hot, contains 12 volts either via the ampere gauge or directly from the battery would connect here.<br /><br />Terminal "S" - The wire that leads to the starter solenoid connects here.<br /><br />Terminal "I" - The wire that connects to the (+) side of the ignition coil connects here. Also, any component such as power to the choke switch, power to the ignition ON light, anything that should have 12 volts applied to it when the key is ON connects here.<br /><br />Unfortunately when one deviates from the original factory specifications, whenther it be mechanical or electrical, the result is what a mechanic usually refers to as a Mickey Mouse arrangement. This is something that is quite difficult to explain or correct without actually being there.<br /><br />I'd suggest that you have the previous owner explain exactly how he had the engine wired.