95' ignition switch diagram?

[regal1975]

Figured I would simplify things here so you dont have to red all of the below in case someone has this handy.


Does anyone have a wiring diagram for the ignition (KEY) switch for a 1995 Johnson 40 which shows what each wire on the switch should read?


I just purchased a boat with a 1995 model 40hp johnson motor. The motor has run fine in the past except for the power pack. I purchased it in a non-running state, and replaced the coil and the powerpack. Still no go. It will run if I disconnect the red plug inside the engine and start it at the starter (bypass the ignition switch. This leads me to think the new powerpack is working fine. I can turn the engine over using the ignition switch, but it will not run. This leads me to believe that the starter switch itself is not sending 12v to run the motor (iow either a wire is bad, a connection is bad, or the switch is bad). The Kill switch has been bypassed as well and the bypass is functioning properly. I checked and replaced the 20A fuse in the engine itself as well. If I could find the wire which should be sending 12v constant to the motor I could simply put in a switch outboard and prevent this problem from happening again and prevent the boat from getting stranded again.

Though this problem did lead the previous retired owner to sell the boat cheap so he wouldnt have to deal with this happening again....


Thanks!

 

[Chris1956]

Re: 95' ignition switch diagram?

regal, Those motors ground the powerpack to kill the ignition. They do not send power to the powerpack from the ignition. That is why when you disconnected the red plug, the motor ran. It sounds like you either have the wrong ignition switch, it is faulty or it is wired wrong. If you examine the ignition switch, one pole should be marked M for magneto. There may be another M pole, which would be ground. The ignition switch should connect these poles, when the switch is off, and disconnect them when in the start and run position.

Sounds like you could use a manual...

 

[regal1975]

Re: 95' ignition switch diagram?

yeah a manual would be very nice...

the motor has run fine for years (boat has been in my family since 97), and it is something that died all at once while underway... so it cant be a failed part... Ill go shoot the wires you listed ....

 

[regal1975]

Re: 95' ignition switch diagram?

checked and those wires are functioning properly...

sooo... what wire from the power pack is grounded to kill the engine? If I can put a switch on this wire to open that circuit for running and ground it to kill it then this would accomplish my goal as well right?


I tried removing the "m" wire which goes to the engine (the other goes direct to ground) . This just prevented the engine from turning over. It still reads a ground even when disconnected from the key switch, so im guessing this wire shorted to ground somewhere between the switch and the powerpack then? Or is it supposed to read a ground when isolated from the switch for some reason?



Also.. what type of manual would i be looking for?



Thanks!

 

[regal1975]

Re: 95' ignition switch diagram?

just dug a little deeper.. .different magneto wire... the one which goes to the magneto is working properly...grounding with key in off position, open circuit with key on...

only mystery wires now are the ignition wires.. purple and purple white........ one reads 12v with the key in the run and start positions.. the other gives me nothing, but if i send it 12v it pops the main battery fuses apparently... perhaps this is grounded somewhere it shouldnt be? but it seems that it would pop these fuses every time i try to start it otherwise...

 

[regal1975]

Re: 95' ignition switch diagram?

ttt... im really getting desperate... about ready to convert to pull start...

 

[ezeke]

Re: 95' ignition switch diagram?

What usually causes the problem is that the connector on the emergency kill switch weakens and closes the kill circuit, which it shares with the ignition switch.

Don't put voltage to the ignition wires to test. If you put it on the black and yellow wire, you destroy the powerpack, for instance. Use an ohm meter instead.

 

[regal1975]

Re: 95' ignition switch diagram?

kill switch is out of the circuit.. with that diagram i was able to shoot everything.. nothing in the switch is bad.... all of the wiring is fine... so why is it that the motor will run if i jump start it without the red plug connected, but will only turn over if the red plug is connected???


thanks again everyone!

 

[regal1975]

Re: 95' ignition switch diagram?

checked the wiring at the terminal block over the coil and everything appears fine as well.

It isnt getting spark when the red plug is connected, and it does get spark when it isnt. Wouldnt this mean the coil and powerpack are working?

I am totally lost right now...

 

[ezeke]

Re: 95' ignition switch diagram?

That tells you that when the plug is connected, the black and yellow wire is grounded... somewhere.

Disconnect only the black and yellow wire; it is supposed to have a separate plug at the engine.

 

[regal1975]

Re: 95' ignition switch diagram?

problem solved-ish.... not getting a ground anywhere im not supposed to with the factory harness connected, but chopping the wire right past the power pack solves the problem... running a new wire from there to the key switch to replaced the existing one which is inside the factory wire harness.. Fires right up like always now.


Thanks a ton!!!

should be out on the water tomorrow!

 

[Chris1956]

Re: 95' ignition switch diagram?

Regal, I have had much the same issues you have on my '98 Johnny 150. Somewhere in my motor's past (i bought it used), it had a heavy duty short circuit, where a bunch of current went thru the ground wire and melted off it's insulation in some spots. It also melted off insulation on other wires, and intermittantly shorts to some of them. The other day, I had the purple wire decide to short to ground. Took a bit to find it. Of course, repair took five minutes....