Kind of a first for me.

[CancerKiller]

Have a 2013 RT188, 115 Merc ProXS. Love this boat. It does everything well. Love it. Anyway. Left it in the water for 3-4 weeks because I hurt my back. I should have taken it out but Indidnt. Anyway. I went to take it out today and idled around for a while then throttled down and was running it to get some gas through it and after running it for about 2-3 minutes I noticed it started to kind of lurch forward with throttle open. Motor never hesitated or anything like that. Motor sounded and ran fine. Felt more like prop slipping or hitting a big air pocket or something like that. Did it several times. I’m wondering if maybe it’s everything sitting in the lake for a few weeks. Not sure. I’m gonna add some fuel stabilizer and sea foam and leave it out of water for a few weeks. Not sure what that’s about. Any thoughts?

[jml]

Doubt sitting in lake a few weeks had anything to do with it. Sounds like your prop is slipping.

[Mechanic Bob]

I would recommend you run it at least 10 minutes or more at 4000 -4500 rpm
I asked Don once what is the recommended RPM I should run my motor at as I do not want to go WOT because of debris in the river I fish. He stated that rpm range.
Also talking to a Yamaha dealer and he was stating the same.
This way the motor gets to and stays at operation temperature.

[GeauxTide]

I hope you didn't leave your gas untreated for a month. I've been using Berryman's Chemtool B12 instead of Seafoam for years. Same result and half the cost. Add a can to your gas and run it from 4500-5000rpm to burn most of the old gas out. I use Startron Fuel Treatment and Ring Clean products, also.

[FloridaFlyer]

You need to watch your tach and report to us what the tach is doing during all this. It could even be plugs or a carb problem. Air leak in the fuel hose can also cause similar problem.

[CancerKiller]

I’m gonna fill up the tank & run it and see what happens this week