1987 3.0L Mercrusier Whine

[meder24]

Every time i start my boat from a cold start, I get a whine sound for about 5 minutes. I originally assumed this was the alternator or water pump but the belts look good and everything appears to move freely.
I have seen a few threads on here that mention a problem like this and some say this is just the alternator working harder to replenish the battery due to the start or any power that was lost by sitting.
Can anyone confirm this or is this something that I should be concerned about? I realize this is an old boat and motor but it has been well taken care of and routinely maintained.

 

[Alumarine]

Best if you can pinpoint where the sound comes from.
The handle of a large screwdriver pressed against the side of your cheek bone works well as a stethoscope.