Yamaha 90 issue

To start, the engine is a 2006 90 hp two stroke Yamaha with less than 1,000 hours. A couple of weekends ago I was fishing for five hours or so, moving from spot to spot, without issue.

On the last spot I was anchored for 30 minutes and was ready to move, but when I turned the key nothing happened. No noise, no clicking, no cranking, nothing. The kill switch was fine, there were no obstructions, and everything else on the boat worked fine (live well, lights, GPS). Also, there was no alarm or any indication that it was over heated or low on oil (though I checked and the oil was fine).

So, I pull the cowling off, take the fly wheel cover off and tie a rope around the fly wheel and crank it up. It started fine, but I didn’t want to push it so I headed back to the ramp, without issue. At the ramp I tried to start it on the trailer and the engine was tilted up. It still didn’t crank, but the motor alarm did come on this time.

I took it home and didn’t mess with it for a week and then yesterday tried to start it and it cranked up right away and ran fine. I did a search here and couldn’t find this issue. It is weird that the alarm didn’t come on when I was on the water, but did back at the ramp with the motor tilted up and then cranked fine a week later. It sort of sounds like an over heat issue, but I am not sure. Thoughts?

I doubt it would have cranked with a pull cord if overheated… Did you check your battery connections, mainly the negitive post?

Key West 19’6" CC 115hp Merc
14’ Fast Craft w/ 60hp Merc

not only battery connections, but cables themselves
also, that motor has a main relay, and if its going bad, that could be your problem


Have same motor. Had similar issue. There are 2 neutral position sensors on the motor. One is in Yamaha shift box. Other is under cowling. Plunger type plastic switch that clips on a bracket on starboard side in throttle linkage. Mine was cracked and was not engaging. Simple fix just remove the one under cowling. Yamaha added the second one when manufacturers started using more after market shifters.

The fact that it started on the rope may point to a different problem though. The alarm while tilted up may have been the low oil alarm.

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