Noisy water pump? 4.3MPI

[Superjetjim]

Hi, I have a 2005 4.3 MPI MerCruiser that sounds a little strange. Does this sound like it is coming from the water circulation pump? Hard to tell when listening to it.

I’ve replaced the alternator and it still sounds the same (that wasn’t charging hence the swap out) also the tensioners spins freely by hand / no noise.

Perhaps I could run the boat minus the belt for a few seconds to see if the noise goes away if water pump not turning?

View attachment IMG_7225.MOV

 

[Rick Stephens]

Run it without the belt.

If still noisy, use a fancy mechanics stethoscope (a 24" broom handle) and hold it to components and your ear to locate where the noise is located.

 

[Dubed]

Run it without the belt.

If still noisy, use a fancy mechanics stethoscope (a 24" broom handle) and hold it to components and your ear to locate where the noise is located.

Can you sell me one of those stethoscopes? I dont want to pay more than $50.00 plus shipping....

 

[Bt Doctur]

Take the belt off first, no need to buy anything yet. Simply turning the circ pully by hand will tell you if it is the problem

 

[Superjetjim]

Quick update on this one, took the belts off tonight and fired it up - sounds the same.

So I’ve ruled out the alternator, power steering pump and water pump…

If this boat has a noisy gimble bearing could that noise make this sound?

Any ideas what else it might be?
View attachment IMG_7247.MOV

 

[Stinnett21]

Not sure I hear anything wrong with it. My 5.0 MPI makes a lot of noise down in there also. it has for 1500 hours.

 

[Rick Stephens]

Use a broomstick and find it.

 

[flashback]

Use a broomstick and find it.

You have to go to Hogwarts to learn that skill!

 

[Rick Stephens]

Well, it's either locate the problem using magic or whatever or ignore it. Poster's choice. No one can tell him what the noise is from 2500 miles away until something breaks - then it's easy. Just like magic.

 

[flashback]

I know, it works very well! It's how I kept my 57 ford running when I was a kid..

 

[Bt Doctur]

Well, when was the drive off for service last? Is there any water leaking into the boat?