What makes this kind of noise?

[sailsail]

We had just gotten into the Chesapeake, still motoring at about 5 knots. All of a sudden there was the weirdest sound....it seemed like it was coming from under the rear of the boat.....sounded like either a cat or maybe even a small dolphin crying.....about 10-15 times, randomly. We powered back and the noise stopped. We accelerated and it did not make any more noise.

After a beautiful sail on the Bay, we headed back to the marina without any problems.

But what could have caused it? Obviously there was no cat 20' under water. I have never seen a dolphin in the Rock Hall area. So rationally, it was something mechanical....but what?
We didn't have time to do any troubleshooting today. Just wondering if anyone has any ideas.

 

[dparilla]

First guess...Possibly a belt? Line wrapped around the shaft? Worn Cutless bearing? Engine mount starting to fail?

 

[RichH]

I just recently passed through the mid and upper Ches. I did spot dolphins near Bloody Point & Sharps Island, just a few miles from RH. Usually, one sees dolphins very rarely north of Solomons Island; but, this year is strangely different - could be because of the drought and the high salinity.
There are lots of dolphin this year in the mid bay, more than 'usual'; ditto massive numbers of small swimming crabs.

FWIW - I also got another total body viral skin infection/rash from swimming in the Upper Bay. In some places in the Upper Bay the water is extremely turbid.

 

[Slow Mo^cean]

I second the cutlass bearing. I had one go out in my 78 Ski Natique and when it was going out it sounded like a couple of whales having rough sex, or dying.... Whichever you prefer.

 

[kloudie1]

A shaft zinc spinning on shaft.. just before leaving the area..
Also. make sure the oil level in the transmission is where it is supposed to be ..

 

[Dubo]

My first question is, did it sound like it was from the engine compartment or something rubbbing against the hull? Perhaps a tree branch randomly spinning with the prop until you slowed the engine. Then it was released. I'd take a dip and see if there are any rub marks on the hull and check everything below the waterline, unless you know for sure it was internal to the boat.

 

[sailsail]

Well, it wasn't a line around the shaft. We just had the motor mounts and belts replaced.
So that leaves us with the cutlass bearing going bad, the zinc going bye-bye,or....the dolphin.

The last two would be the most favorable 'problems', altho I do hope we didn't hurt a dolphin. : (
But if it was the cutlass bearing, would the noise continue? We did not hear it again after we accelerated, nor after we took the sails down and started the engine again.

 

[sailsail]

Oh, I like the tree branch idea even better. That would mean nothing needs fixing.

The sound seemed to be coming from underneath the boat, which would fit in with the tree branch suggestion.

 

[Stu Jackson]

We just had the motor mounts and belts replaced.

Have you rechecked your belt tension since "they" did it?

 

[Rick I]

Catfish?

 

[sling]

I'm having trouble getting my 1989 hunter 33.5 to the max rpm looking for any ideas

 

[Dan Johnson]

RichH...

The water in our marina on the North East now is a nice shade of grass green thanks to the blistering sun and lack of rain (until yesterday!)...no one's gotten any dermotology issues so far...

 

[Benny17441]

Have heard the noise before, years ago in a different boat. I thought it was the cutlass bearing whispering it's last words but the noise never returned in the years I had the boat. After a couple of months or so I stopped listening for it and had forgotten all about it until this post.

 

[Andy1237]

Couid you stuff box gotten hot from being too tight? When you back off it cooled down and quit squeeking?

 

[sailsail]

Sling,
Could it be barnacles on the prop?
We had the problem a couple years ago. Someone suggested we get a diver. We laughed at them, but eventually decided $60 for the diver was a good deal. And it solved the problem!!!
With all the heat we've had, people haven't been taking their boats out as much, so there is a lot of 'stuff' growing on the bottom of the boats also.