https://youtu.be/k1GvxDL6jfM


I'm getting a higher pitched noise from the rear of my 502 MAG MPI Bravo on my Baja 232. Had to replace water pump impeller and housing this year, as well as a power steering pump (bad bearing), so I've had my head in the engine compartment checking on things more then I normally would have. Not sure if this noise is new or been there a while.
It's most noticeable at the back PORT side of motor, near the back. It sounds like a bearing noise, and I suspect its the coupler. I disconnected the serpentine belt briefly to make sure it wasn't belt noise or one of the pulleys transferring the noise. Does not seem to change going in/out of gear, seems RPM related.

Sorry for the camera work, was just trying to get microphone to best pick up the noise.

Might just be the way its been. I've only owned this boat since August 2016, and its been in storage for the winter.

Would any internal engine parts failing make this noise? As mentioned I had a seawater pump issue. No alarms or anything, but I think it wasn't flowing any water at idle, but at speed water was being forced up. Not sure, just saw some temperature gauge weirdness on its first run for the year and dug into the issue.

Internal flappers in the exhaust can sound like a knocking bearing.

I wasn't concerned with the knocking. That's the exhaust noise the camera is picking up. Its the "Whirrrr" kinda noise you can hear. A bit higher pitched.

Have you serviced/checked the gimbal bearing?

Not yet. But Gimbal or Coupler were my initial thoughts if this is not a normal noise.

Pull the drive and run engine. It could also possibly be drive noise transmitting thru shaft. Gimbal bearings usually sound rough. Not whiney like a power steering poump.

My first thought would be gimbal bearing/drive noise.

You could do what my mother does when she hears a weird noise - turn the radio up

Couplers don't make any noise.

Hmm..
We had a ton of rain last week. The boat is on a lift, but the float switch wasn't working and the bilge was very full of rainwater. I bet it made its way into the transom plate... Didn't think much of it at the time, just flipped on the bilge when I jumped in the boat and while it was pumping, opened the hatch to see a fair amount of water in there still. Bet the gimbal got wet. I'll grease the fittings again and hope it pushes any water out. UGH.

There is a seal before (transom/engine side of the gimbal bearing) but not one after (bellow's side)...so, if the gimbal bearing got wet, you may have water in the bellows. I would be taking the drive off to check this and of course doing this you can check the gimbal by eye and by ear.