wiring question 68' johnson 40

[johnson1st]

I have an 87' bayliner bass boat, 50hp Force is junk, took off and put this johnson 40 on. Trying to wire up. the key switch on bayliner has more than I'm used to: (got engine to turn over, but no fire to plugs?)<br /><br />bayliner switch:<br /><br />B = Battery<br />S = Selenoid "S" post<br />M = points/condenser<br />M = points/condenser<br />I = Not sure???? put to temp sensor<br />C = Not sure???? put to elec. choke<br /><br />p.s. this 40 does not have a generator...<br /><br />on the johnson, i got a manual, all wired up per<br />schematic...wire going to cut out switch on motor is a ground going to "I" post on selenoid...seems strange, I would think that the black wires on cut out switch with fiber washer means "Hot", I would think the "I" wire on selenoid goes here. Anyway no fire....anyone have ideas??? How do I get power to points??? Thanks.

 

[byacey]

Re: wiring question 68' johnson 40

If it's like my motor, the ignition switch shorts both points together to kill the ignition. One set of points is closed when the opposite set opens, so in effect the coils never see a point opening and can't fire. This is a magneto engine and there isn't any power applied to the points or coils, except what is induced in the coils by the flywheel magnets. Applying 12 volts to any of the coil leads is sure to burn up the coil. I don't believe the cutout switch should go to the solenoid. One side of the cutout is engine ground, and the other side goes to one of the set of points.

 

[Paul Moir]

Re: wiring question 68' johnson 40

It's just like byacey's<br /><br />The solenoid actually does hook in at the base of the vaccum cutout switch, which is in turn grounded via the neutral/throttle saftey switch (which prevents the engine from being started with the throttle too high).<br /><br />Disconnect the two wires that come down from up underneath the flywheel - one goes to the vaccum cutout switch center post, the other should just go straight to the keyswitch. Crank the engine and see if spark returns.

 

[johnson1st]

Re: wiring question 68' johnson 40

Thank you both, I'll try disconecting the neutral safety switch wire. Been working on another project. And winter is on the way, don't know if I'll get it in time for another outing ...but thanks and i'll keep trying.

 

[johnson1st]

Re: wiring question 68' johnson 40

Paul,<br />I un-hooked the plug in at the cut out switch. You are right, fire is back. So does this mean that I have a wire from switch not correct, or does it mean the cutout switch is bad? Let me know what you think, and thanks for the fire!!!

 

[Paul Moir]

Re: wiring question 68' johnson 40

Ok, that means the black wires are connecting to the wrong place somewhere. They should run out the engine (after one first connects to the tip of the cutout switch) and straight up to the keyswitch where each connects to an "M" terminal. If the wire shorts to ground somewhere or the black wires short together, you'll loose spark.<br />The kill switch stops the engine by shorting the two wires together when it's in the "off" position.<br /><br />A bad vaccum cutout switch would be beyond rare. It's almost a "can't happen" thing.<br /><br />The "I" terminal is for a different kind of engine than your outboard. Just forget about it & don't hook anything to it. The temp sensor wire is a ground for a light you put on the dash - when the engine overheats the light comes on. "C" is for the electric choke - you've got that one right.

 

[johnson1st]

Re: wiring question 68' johnson 40

the only 2 wires on the outboard harness are what I hooked to the 2 "M" terminals on the switch, one a blue wire, one a white wire. They really should be right from what I see. There is a black wire coming from switch that I hooked to a soldered on ground wire on the selenoid bracket, that's the only way I could get it to turn the starter. Unless you can think of something else, that I'm missing. I really can't run the engine with the black wires unhooked at the engine...???<br />But I'd like to get it running before the cold hits, just to ease my mind on my purchase.

 

[itstippy]

Re: wiring question 68' johnson 40

If all you want to do is get it running you can disconnect all the wires, put the lower unit in a barrel of water, and use jumber cables directly to the starter. It will run if it will run. It's a magneto ignition system and the only external 12 volt power you need is to turn the starter to get it going. After that it needs no battery whatsoever. If you do this hook the jumpers black from a bare spot on the motor (ground) to battery negative; red from post on starter and touch to battery positive to turn the starter. You'll have to choke it to stop it.<br />If you want to wire the motor correctly you should hang on every word Paul Moir says and follow his advice to the letter. Paul is a Grand Master of BigTwins. Here's the type of thread you get when Paul and a couple other BigTwin enthusiasts (CATransplat & Lark2004) get to helping a new BigTwin owner:<br /> http://www.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=28;t=034543 <br />Worth bookmarking, I thought. Good luck and welcome to the BigTwin club!