Outboard Electrical Problem

Hoping somebody might be able to point me in the right direction.

I have a 1999 Lund Pro Sport 1700 with a 1997 Johnson 115hp. A couple of trips ago I blew a 20 amp fuse under the motor cover. I replaced the fuse (there was a spare in a storage holder connected) and didn’t have any problem for probably at least 24 more starts. Then this weekend the fuse blew again. I replaced it and it blew again as soon as I tried to start. I made several attempts before I concluded that it wasn’t going to be that easy this time.

I checked the wiring the best I could at the time and did not observe any obvious damage. Then I tried a 30 amp fuse to see if I could get anything to work as we were a long way from the ramp. The 30 amp fuse did not blow but the motor did not turn over either. The ignition key switch then got very hot.

What should I look for and how do I fix this?

If it were me, I would look for a good Johnson mechanic. If there are no worn wires anywhere, it sounds like something beyond my abilities.

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If it were me, I would look for a good Johnson mechanic. If there are no worn wires anywhere, it sounds like something beyond my abilities.

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I was afraid that is probably what it will require but I would like to give it a try on my own. I will take another look at the wires now that I have the boat on dry land. I like to learn what I can so maybe the next time I can fix it and not have to have my fishing day cut short.

You have a ground wire problem….

Dog

I dealt with a similar issue on a motor I owned a few years ago. It was an Evinrude, and roughly ten years older than the motor you’re got, but it was the stubby 20A fuse under the hood that kept blowing. It was totally unpredictable … I’d go days without a problem, then I’d have to replace three fuses in a day.

First thing I did was pick up a half dozen repacement fuses (it took some searching, but CarQuest had them).

My problem turned out to be a wire that was up under the console. The wire was routed from the outboard, and eventually ran through a round hole cut in the aluminum just in front of the throttle. The insulation on the wire had finally worn off to the point that the wire would occasionally contact the aluminum and short out, which took out the fuse under the hood.

I can’t tell you how many electrical “problems” I “fixed” before I found that wire. The half dozen fuses I bought turned into more like 20 before I finally solved the problem.

You’ve clearly got a short. It will probably take you or a shop hours to find it since it’s not consistently shorting out. I’d recommended picking up a bunch of fuses, determining where the wires are routed between the outboard and the console, and systematically checking every place where a wire could be shorting out to the hull before you do anything else. I wish I had done that first!

When you find it, you’ll probably only need a few pieces of electrical tape to solve the problem. Good luck!

Well I searched and searched and could not find any problem with the wiring. I decided that the problem must be in the ignition switch itself or in the motor. In order to attempt to narrow things down, and hopefully solve the problem, I replaced the ignition switch. That wasn’t it.

Apparently while tugging and maneuvering wires while installing the new switch I exposed a pair of wires that weren’t connected to anything and weren’t capped. I separated and taped the wires. Ta da, I am back in business!

that would do it. Glad you found it.