Rattle from stern, 2012 SX190 --what should I check?

[IvanRZB]

Hello all,

The last few times I've taken her out I've noticed a metallic-sounding rattle at the stern, reading through various forum threads it seems like this is something I should really check on. I've read some threads on wear ring issues but I'd like to get the forum's advice before I tear into anything.

When I stand on the upper swim platform--above the cleanout port--the rattle sounds like it's coming directly underneath me. Best I could describe it is that it sounds like there is a jar full of quarters down in there. I mostly hear it at idle or low speed when we first start the engine, I don't think it's there at higher speeds but that could be because it gets drowned out by engine noise. The rattle is definitely gone after some run time, and also not apparent even if we've anchored at a cove for a while (~1 hour) and fire the engine back up.

At first I thought it might be the steering and bucket linkages as they have some play and they make a similar rattle when I shake them by hand, but that wouldn't explain why I don't hear it after things have been running for a while.

What should I look for to make sure I don't have a larger issue developing? How far do I need to tear into things?

Thanks in advance!

 

[Scottintexas]

does it make the sound if you start it on land?

I might remove the manhole cover near the cleanout and see if it gives any clue,
If you've ruled out the bucket/nozzle vibration then it's either going to be the shaft/coupling or the impeller/wear ring or the cone nozzle,

have you ever removed your impellers before? have you ever checked your cone bearing?

 

[Cobra Jet Steering LLC]

Pump liner swelling, Run it on the trailer and spray some w d 40 into the impeller area while it is running if the noise goes way down when you spray the wd40 you have your culprit.

 

[IvanRZB]

does it make the sound if you start it on land?

Not sure, will try it

have you ever removed your impellers before? have you ever checked your cone bearing?

Negative, I've had the boat for 1 year and have only done minor maintenance. I've done a good bit of work on cars, this is my first boat so still learning.

Pump liner swelling, Run it on the trailer and spray some w d 40 into the impeller area while it is running if the noise goes way down when you spray the wd40 you have your culprit.

Will try this, thanks

 

[Cobra Jet Steering LLC]

The pump liner swelling is very common ,you can also look inside the pump and see the dark spots on the liner where the impeller rubs, and you can see the contact between the impeller and the liner, you will usually notice the longer it sits without being used the more it makes noise or even slows down the starter, in extreme cases it will actually lock up the pump and keep the engine from starting.

 

[Julian]

Sounds like reverse gate chatter to me....but you say it happens in neutral too, so that rules that out.