power loss and shaking motor

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robertciboats

Recruit
Joined
Jul 4, 2026
Messages
2
I have this 2015 Mercury 150HP 4 stroke that runs perfect at low idle and at 2200 RPM loses power and shakes like in the video. Any suggestions would be great.
 

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Jeff J

Chief Petty Officer
Joined
Jun 23, 2021
Messages
579
I don’t think I have ever run one that hard without the prop spinning. Losing power at higher rpm is generally a fuel restriction. Most commonly a fuel filter that needs changed. But could be elsewhere or even a failing fuel pump.

As far as the shake… no clue unless it just the exhaust gases blowing against something in the water. Did it shake that way running across the water?
 
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Jeff J

Chief Petty Officer
Joined
Jun 23, 2021
Messages
579
A bad prop or a bent shaft can make it shake bad enough to put a motor into limp mode. Of course, the prop needs to be spinning for that.
 
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racerone

Supreme Mariner
Joined
Dec 28, 2013
Messages
39,729
Some of these 4 strokes can NOT be revved up in neutral.----ECU prevents this.----Test with it in gear and post a video of a test run.
 
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Jeff J

Chief Petty Officer
Joined
Jun 23, 2021
Messages
579
I didn’t know they had started limiting the throttle that way.

I just came from the dock. The shift release button on the throttle was stuck in. I don’t know why someone felt the need to push it but I spent 2+ hours in 105* heat index fixing it for them. I had to break the button out of it without the benefit of a drill. Anyway, I was worried I broke something else be cause it went from easy movement F-N-R to refusing to come out of neutral. Shifts easy with the motor running. I have always reached over the side and bumped them into gear when they bring them for impeller change. I guess I won’t be doing that on the new ski boats (20’ Sea Rays with 150 EFI motors).
 
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