serious "chatter" in stern

[palmbeachboater]

33.5 Hunter has serious "chatter" noise when in gear. Much worse noise when turning...very loud noise. It's not the engine; not the transmission. Nothing caught on the drive shaft or propeller. You can feel a vibration when placing hands on the stuffing box. I just had the cutlass bearing replaced. Anyone ever had the same problem? Any ideas? Recommendations? What to look for? Thanks,

Malcolm, Palm Beach, Florida.
macleodpb@aol.com

 

[Ralph Johnstone]

I just had the cutlass bearing replaced.

Seeing as how you just had the cutlass bearing replaced (and everything else is in order), that would be my first suspicion.

Can you check for lateral movement (at the prop) of the shaft ? There should be no movement if the bearing is new.

Also, seeing as how you're down there, you may want to check the prop on the off chance it may have worked its way loose.

Let us know what you find.

 

[walmsleyc]

Check you clearances around the shaft log. The engine will lean on its mounts when you turn, and if your shaft is not perfectly centered going through the shaft log, then you can get a knock that gets worse when you turn.

I had this problem, and experienced the same symptoms as you have described. Upon inspection, my shaft was very close to the bottom of the shaft log. Probably due to the age of my motor mounts (compressed with age). If the engine was running a little rough, or I was taking a turn, the shaft would knock quite loudly against the log and you could feel it through the whole boat.

Chris

Seeing as how you just had the cutlass bearing replaced (and everything else is in order), that would be my first suspicion.

Can you check for lateral movement (at the prop) of the shaft ? There should be no movement if the bearing is new.

Also, seeing as how you're down there, you may want to check the prop on the off chance it may have worked its way loose.

Let us know what you find.

 

[s sauer]

Engine alignment

I'd disconnect the shaft coupling and do a re-alignment in the water.

 

[DStegs49]

RE chatter

I have the same problem. It is possibly from the bearing in the stuffing box. Possibly worn because of the age of the boat and compression of the motor mounts. I had also replaced the cutlass bearing. I checked at the Hunter Owner store but haven't found one yet. I plan on posting my problem also to see if anyone has a part number or solution for me. Good luck.
Dave

 

[kmart]

I have the same problem. It is possibly from the bearing in the stuffing box. Possibly worn because of the age of the boat and compression of the motor mounts. I had also replaced the cutlass bearing. I checked at the Hunter Owner store but haven't found one yet. I plan on posting my problem also to see if anyone has a part number or solution for me. Good luck.
Dave

Had similar issue. My boat was just hauled for the winter. When I went to inspect prop and strut I noticed that the zinc cone on the prop had worn enough that the screws were not holding it tight to the prop. When in gear it would bang and Make an awfull racket.

 

[robertsapp]

As mentioned above, check your alignment and make sure the shaft is centered in the shaft log (you might have to haul the boat and pull the shaft seal to be sure, but you can get a rough feel by disconnecting the coupler and moving the shaft around by hand and see how far you can move it before you encounter resistance). A knock or clank when motoring, especially when it occurs even at low RPM, usually means there's inadequate clearance somewhere in the driveline and something is hitting something else. After I replaced my motor mounts last year I initially aligned the engine to the coupler, but didn't ensure the shaft was centered in the log. I ended up with a godawful clanking noise when motoring because the shaft was contacting the inside of the log. On my next haulout I was already planning to do a bunch of other driveline work and I used it as an opportunity to make sure the shaft ran true through the cutless bearing and was centered in the log. I blocked it in that position and then aligned the engine to that, and haven't had any noise since.

 

[Ken13559]

As mentioned above, check your alignment and make sure the shaft is centered in the shaft log (you might have to haul the boat and pull the shaft seal to be sure, but you can get a rough feel by disconnecting the coupler and moving the shaft around by hand and see how far you can move it before you encounter resistance). A knock or clank when motoring, especially when it occurs even at low RPM, usually means there's inadequate clearance somewhere in the driveline and something is hitting something else. After I replaced my motor mounts last year I initially aligned the engine to the coupler, but didn't ensure the shaft was centered in the log. I ended up with a godawful clanking noise when motoring because the shaft was contacting the inside of the log. On my next haulout I was already planning to do a bunch of other driveline work and I used it as an opportunity to make sure the shaft ran true through the cutless bearing and was centered in the log. I blocked it in that position and then aligned the engine to that, and haven't had any noise since.

So essentially when doing shaft alignment, one would lift the shaft to about center of the shaft-log and adjust the motor mount to suit. Right? I'm planning to replace the Buck Aq..hose and will have to realign everything there I suppose.

 

[robertsapp]

So essentially when doing shaft alignment, one would lift the shaft to about center of the shaft-log and adjust the motor mount to suit. Right? I'm planning to replace the Buck Aq..hose and will have to realign everything there I suppose.

Yes...but. To do it right, your alignment actually starts with the strut and Cutless bearing. If everything is where it should be and nothing's been damaged, your shaft should be positioned so that it passes straight though the Cutless bearing. If the strut is properly aligned to the shaft log, then the shaft should then pass through the center of the log. You'd then block it in this location (I use a chunk of rigid foam to support the shaft because it's easier to carve a notch in it than a chunk of wood) and then align the coupler using the engine mounts. Where things go astray is if your strut isn't aligned properly to the shaft log, which can happen if someone has ever wrapped a line around the prop and seized the engine while motoring, for instance. In that case, aligning the shaft to the center of the log might actually misalign the shaft with the Cutless bearing, introducing lateral forces at the bearing and putting a slight bow in the shaft, which you'll feel as a vibration when motoring. That's why the best way to do this is when the boat is out of the water and you've pulled the shaft seal. That way you can start at the Cutless bearing and work all the way forward and make sure everything is in alignment. But generally it's a good idea to make sure the shaft is centered in the log, and if it's not, you can get some nasty clanging while motoring.