Getting shocked by my outboard

[InfantryWeaponsOfficer]

I took my 1978 Johnson 35 HP Seahorse off the transom of my pontoon boat in order to replace some wood under the aluminum transom skin. I did not disconnect anything from the outboard other than the fuel line. I simply hung the motor from a support constructed from an automobile engine stand taking care not to put the steering cables or electrical wires in a bind or strain. Clearly I failed.

After re-assembly the engine starts and runs just as before but will not shut down. Neither the key switch nor the safety lanyard switch will kill the engine now. I wasn't overly concerned at first because the engine has a manual choke and I was able to choke it dead easily enough. Obviously I have loosed a ground somewhere in the system and just haven’t located it yet.

The more pressing problem at the moment is the propensity of the engine to shock the wee out of me every time I touch it. I am a recently retired Marine Corps Chief Warrant Officer so as you can imagine the shock usually elicits a string of profanity that would make the average Petty Officer blush, it would no doubt kill an Airman. We use a public launch facility, enough said.

I have a manual and wiring diagram but electricity is not my area and it makes about a much sense to me as Chinese Algebra. I’d like to take one more stab at it before taking it to the mechanic. Any help would be greatly appreciated.

Gunner

 

[Will Bark]

Can't help you much but check all the wires under the cowl for insulation cracked and touching the engine block which is sending voltage thru the steering cables; I've been there and that's what I found. Hope this helps.

 

[kbait]

There's a ground cable near the starter motor that grounds powerhead to chassis. Make sure connections are clean/tight. Does the motor misfire when shocking you? If so, check wires from coil to plug for arcing.

Good luck!

 

[SolingSailor]

Yes, I think if you are feeling an electrical shock there must be a spark plug wire with bad insulation. The 12-15 volt battery/charging voltage would not be enough for you to feel it.

 

[JDusza]

+1 kbait.

 

[81_chapparel194]

I had this same problem but mine just showed up out of the blue. but would only shock me thru the key. I would touch the key to turn it off and would get the daylights zapped out of me. and the key wouldn't kill the engine. (not sure of engine shocking me as I never touched the engine) but if felt like 110 volts ac biting. my problem was I had a bad coil that was arcing to the ground wire on the coil and feeding voltage back to the ground wire back up to the key switch not allowing the key to turn it off. and shocking me in return. replaced that coil and had no more trouble. easy to check remove cowling in a dark garage start engine and look for the lightining storm.. maybe this helps.btw mine was an 81 90hp

 

[MaPaHa]

My 140 evinrude did that a few years ago and it was the ground wire that kills the ignition that is located by the starter. It could be anywhere in the ground wire from the shifter box to the case ground at the motor. I cant say if my motor shocked me but it was my steering wheel to my control box that got me. The lack of ground on the control box made it hot and when i touched it and the grounded steering wheel it lit me up. Had to sit down for 20 minutes or so. It's one heck of a nasty shock!!!

 

[F_R]

The spark plug wires aren't the only high voltage present. The Black/yellow stripe kill wire carries 300 volts.

 

[MikDee]

Try using resistor spark plugs, they have a tendency to eliminate arcing, crossfiring, & random spark leakage by sending it all to the firing tip, especially if you have metallic core spark plug wires.

 

[Vic.S]

Try using resistor spark plugs, they have a tendency to eliminate arcing, crossfiring, & random spark leakage by sending it all to the firing tip, especially if you have metallic core spark plug wires.

Do not use resistor plugs with OMC CD ignition.
​If you want suppressed plugs they must be inductively suppressed which normally means the Champion Q series. For the engine in question QL77JC4

 

[daselbee]

If you are getting shocked, AND the engine will not shut down, the problem is very likely in the black/yellow kill wire. If that wire is broken, and touching any part of the boat frame that is not grounded, then you will get shocked.

Very typically, the black/yellow will break inside the control box, the engine will fail to shut off, and the user will get shocked when touching the key....

 

[boobie]

Agree + 1...................