Outdrive "humming"

[Sanmiam]

So I noticed a strange sound earlier that I cannot wrap my head around a cause. It almost sound like the blower is on, but it is coming from the outdrive.

1) It does not occur when the boat is in neutral, only in gear (forward or reverse)
2) The sound does not change with speed, RPM

Any suggestions? I would think gimble, but it does not occur in neutral, nor whine at full lock. It does not have any sort of click or knocking that I can hear. Drive fluid is at normal level.

Any ideas?

 

[toofast]

Can you provide a few more details....

What year, what kind of out drives, assume single...also what engines you running.

 

[Sanmiam]

Sorry,

07' B3. 496mag. Def not the engine though.

I took it out again and the sound does change pitch based on RPM. Sound kinda like a bad bearing.....

 

[AllDodge]

Sound kinda like a bad bearing.....

Yours might not be the case, but the hum is what caused me to repair my own drive the first time years ago. Heard a slight hum and later turned to a very slight rumble sort of. Turned out to be the upper needle bearing under the cap had gone out. Drain some drive lube and see if there is any metal in it