2010 225 pro xs loss of power

[KX1990]

So I just recently had the lower unit fluid, impeller, spark plugs and fuel filter service done. Bought the boat used at 159 hours and serviced at 164. Boat ran perfect before the service, however today when I was out on the lake I was at full throttle at around 5600 rpms and after a minute into my ride I noticed a power loss. It started dropping RPMs and went down to 4400 rpms and would not hold rpm. I get to my fishing hole and fish, however when I start up and go to the next spot I’m at full power again and cruising over 5500 rpms. However same thing happens, it bogs down and I feel the loss in power. It surges around 3800-4400 rpms as if I was letting off the gas but I’m still at full throttle. Happened 3 times and called it quits. I did notice that the primer ball was rather soft and I noticed excessive soot in my propeller (more than usual sticky black goo). I only owned the boat for a month now but this is the first time this has happened. Weird thing is that I’m able to go full speed for the first minute or so then the problem occurs.
I did notice that in neutral when I reved the motor it beeped once. Is that normal?
With the smart gauge on with the engine off and I was fishing voltage was at 11.8v is that low? At full throttle I’m at 13.8-14.0v. Could a bad battery cause my power loss issue at full throttle?

Suppose to go out with a mechanic soon for a test drive on the lake to verify problem but I would like an idea about what it could be. Praying it’s not a major part failure, seems like a fuel issue.
Also I’ve read other post about tracker seals, bad compressors, diaphragm seals. Etc but my motor seems to be idling fine and gets out the hole on plane fine but I lose power after a minute or so into full throttle.

Any input would be appreciated.

[Savage]

Never ever rev your motor in the neutral position......it beeped because you over reved the motor in neutral and a fault is now stored in the PCM.

Try pumping up the primer bulb each time you start the motor.

Perform a spark test as the problem is occurring.

[KX1990]

I wasn’t steady holding the throttle in neutral, all I did was a quick burst maybe not even a second. also pumped primer bulb and at the end of the run it would be spongy again

[Savage]

You shouldn't ever rev in neutral, even for a second, that's why the alarm went off. The alarm was the rev limiter that was keeping you from blowing the motor apart.
The bulb should not still be hard after a run. The bulb will only be hard after you pump it up.

[KX1990]

Thanks for the info won’t rev it again in neutral

[Savage]

[SilverFox579]

In my opinion 11.8v is low, especially you started with a fully charged battery and after a run. What specific battery do you have (brand and model #).

Couple FAQ topics you might what to review

FUEL LINES AND PERFORMANCE PROBLEMS

BATTERIES THAT MEET THE REQUIREMENT

[KX1990]

Thanks for the info, will update with battery when I get home from work.

[EuropeanAM]

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