Hours meter doesnt match motor. How to fix?

[duck1]

Bought a 2011 pontoon with a 115 mercury 4 stroke. The boat meter says 47 hrs but when we took it in to be serviced, the mechanic said it had over 500 hrs. Is there any way to set the meter to the correct number of hours?

 

[boscoe]

I will presume that the mechanic extracted the hours that are recorded within the ECU/EMM/PCM. Is this correct?

ECU hours are one thing. Hour meter hours can be something altogether different.

ECU's can be removed and replaced. Hour meters can be removed and replaced. In which case they may never agree.

There are hour meters that run when the key is on but the motor is not running. If you have this type simply turn the key on and leave it on for 453 hours (500 minus 47).