1956 30 HP Johnson Electronics

[jsfinn]

Hello,<br /><br />I've aquired a 1956 30 HP Johnson. I'm pretty comfortable with the mechanics of it, but I don't know a lot about the electronics on it.<br /><br />1. The boat it came off of doesn't have a key or button to start it. I'm guessing that in 1956, they would just hold the battery cable to the battery until it started and then take it off. Is this a bad guess?<br /><br />2. I think this motor has a 6 volt starter. Will I hurt it by using a 12 volt battery? I've read things that say it's ok to do this.<br /><br />3. I want to wire in a key or button to start the motor from the helm. What guage wire should I use between the starter and the switch?<br /><br />4. This motor hasn't been started in a lot of years. It ran before it was put away but then locked up. It freed up easily with some oil and now turns easily. I'll pour some more oil in the spark plug holes before trying to start it and also change the impeller and the gear case lube before starting it. Anything else I should do before cranking it over?<br /><br />Thanks!

 

[Paul Moir]

Re: 1956 30 HP Johnson Electronics

Congrats on the new purchase. That's a glorious old outboard you have there!<br /><br />1.) Not likely - they liked push button starting the same way we did. Can you locate the solenoid? It ought to be in the boat somewhere.<br /><br />2.) The 6v starter is much larger than the 12v one. The 12v ones measure more than 3.5" in diameter. It would be much better to find a 12v starter than to send 12v to a 6v starter. It may work, but not for long. Any starter for a 28-30-33-35 or 40hp, 1956-70s will replace it.<br /><br />3.) The key switch will fire a solenoid, which fires the starter. That way you don't have to run heavy gauge wire up to the dash. That and the key switch won't take the current of the starter. Normally, #16 is run to the ignition switch for the solenoid circuit. The starter, solenoid and battery cables are usually #4 for a 12v system. (Though later systems used #6). Some others:<br /><br />+12v for Accessories: #10<br />Kill switch lines: #18<br />Electric Choke Solenoid: #16<br /><br /><br />4.) Check spark before trying to fire it off. Try to draw a 3/8" long spark.<br /><br />I drew up a wiring diagram for my 28hp which is pretty much the same as for your 30hp. If you would like it email me at:<br />paul.moir@ns.sympatico.ca<br /><br />PS - when talking about a '56 Johnson, 'electrics' seems more appropriate to me than 'electronics'.

 

[jsfinn]

Re: 1956 30 HP Johnson Electronics

Paul,<br /><br />Thanks! You've got mail!<br /><br />The only thing that I can think of is there is pull/push type switch at the very begining of the berth (close to the helm) which I was pretty sure is for the lights. Maybe I'm wrong though. The wire does run to the back of the boat but I figured it was for the stern light. It's just lamp cord for wiring. I'll inspect it closer but I don't think that's it.<br /><br />Will I damage anything by connecting the battery directly to the starter just to see if it works?<br /><br />Thanks again,<br /><br />Josh

 

[jsfinn]

Re: 1956 30 HP Johnson Electronics

Another thing - I guess I don't understand the concept of a solenoid. From what I read, it's just an electomagnetic switch (sorry..I don't know a lot about this stuff - so I'm thinking of a relay). What's the need for it if you've got a switch that you're manually operating (like a button or key)?

 

[Paul Moir]

Re: 1956 30 HP Johnson Electronics

No, nothing will be damaged at all. Just connect your wires so that the spark happens at the battery so you don't blow the threads on the starter post to bits.<br />If there's gas in the carburetor, it should start when you do this.<br /><br />Does your engine have an electric choke? If so, there should be a large cylindrical solenoid (different kind than the starter solenoid) strapped to the bottom of the carb?<br /><br />I'm thinking if you do, that is what the switch is for.

 

[Paul Moir]

Re: 1956 30 HP Johnson Electronics

The (starter) solenoid is an electrically operated switch. This is properly called a 'relay' but with automotive and mechanical things, the archaic term tends to stick.<br /> How a relay works, click here.<br /><br />The electromagnet on the solenoid draws only around 5 amps as opposed to the 40+ amps drawn by the starter. This allows the use of a simple pushbutton rather than a fuse panel sized switch for the 'crank engine' (ignition) switch.<br /><br />The two little terminals on the starter solenoid are the electromagnet's terminals, and the large ones are for the switch in it.

 

[jsfinn]

Re: 1956 30 HP Johnson Electronics

Paul -<br /><br />I don't think it has an electric choke, but I could be wrong. I've spent most of my time working on the boat and haven't done anything with the motor except build a stand for it.<br /><br />I'll post later with more details though.

 

[jsfinn]

Re: 1956 30 HP Johnson Electronics

Again Paul, Thanks! I understand that point of a solenoid now - basically - you don't have a big-honkin-not-very-flexable-ugly wire at the helm!

 

[Laddies]

Re: 1956 30 HP Johnson Electronics

the original solenoid was in a small box that was mounted on the inside of the transom and in later years (super 35 and up) a larger box. It also served as disconnection point for the engine wires

 

[jsfinn]

Re: 1956 30 HP Johnson Electronics

So, this afternoon, I pulled her out and started cleaning off 50 years of dirt and grime. I got some oil in the pivot points and it started moving pretty smoothly. After cleaning up the battery terminal connectors, hooked it up to the battery to see what would happen. As soon as I tapped the positive lead, it cranked over a little tiny bit. After messing around with it for a while, I came to the conclusion that my battery went bad and headed over to the auto parts store for a new starting battery. When I got back, I tried it again - it threw some pretty big sparks and cranked and cranked and cranked. It sounded pretty good too! I feel pretty confident that if I put some gas in it, it'll start right up. (It's too cold now to be messing with water outside - it'll have to wait till spring). <br /><br />The interesting part was when it was cranking over, about 4 good handfulls of what looked like insulation and seeds came flying out of the exhaust port. Must have been an old mouse nest built up in there.