mercury 2015 4 stroke hesitation mid RPM

[stewtn]

Guys got an issue I can't figure out. mercury 2015 115HP 4 Stroke. Starts and idles great. Overall runs great. But at about 2500 RPMS the boat "hesitates" and power is reduced. This happens when I first get going but will go away after the engine warms up and everything if fine. Won't do it again until next time out. I thought it might be water in fuel so I've put Sea Foam and Heat but the problem persists. At the same time I'm noticing a very small oil slick coming from the motor. I pulled the boat out this weekend and noticed 2 things. 1) There is oil in the cylinders, and 2 I saw a spot of oil near the union of the lower unit and upper unit. I've taken pictures of the oil and also of the boat hesitating at 2500 RPMS. (Sorry this was before I pressure washed it).
Here is a video of the boat heisting (BTW this sound different than when it does it in the water in gear) --

 

[QBhoy]

Hi. It’s one of a couple of things. These engines are now known to have issues with the trim sender or limit switch. It causes the rpms to momentarily and occasionally limit the rpms when it thunks for a minute that your outboard is tilted up. It could also be your neutral safety switch in the remote throttle control. These can fail too. If it thinks it’s in neutral then it will limit the rpms to 2500 rpm

 

[stewtn]

I'll look into that! Seems odd to be a switch failure when it goes away after warming up.

 

[QBhoy]

I'll look into that! Seems odd to be a switch failure when it goes away after warming up.

Yeah. But it’s sure a thing, I’m afraid. Also can be caused by the cables inside the remotes binding up and causing issues with the neutral switch. There is also a shift switch under the hood that can get knocked by a loose or coming loose fixture on the cable assembly next to it.