View Full Version : Noise from prop/shaft

06-23-2005, 09:27 AM
Need a little help. When shifting boat back into neutral, I get a high pitched sound coming from what sounds like to prop. Best way to describe the sound is what it sounds like when you run your finger around the top of a water glass and get it to sing. Only notice it when shifting to neutral, and as soon as the prop comes to a halt it stops. Sounds to me like the thing needs lubed, almost like it is rubbing metal to metal. Do you guys lube the prop shaft on a regular basis? Anybody else had this issue?


06-23-2005, 09:51 AM
No real clue but you might look for fishing line jammed in there someplace.


06-23-2005, 11:20 AM
I think water is supposed to lube the strut and packing gland. The packing gland may be a little tight. Also, check the prop shaft strut for any visible signs of damage like maybe you struck a floater or something. You can try to spin the prop by hand while the boat is on the trailer. It won't spin freely, but it should turn. If it's really really stiff, or won't turn at all, a trip to the boat doctor may be in order.
Hope this helps

06-24-2005, 04:42 PM
Thx guys. I did call my dealer, who I just had adjust the packing gland. His mechanic told me to give it a while as the rope needs to soften up a bit. I know a little water is coming in as it should, 1 drip every 45 seconds. May be a little tight, but we'll see.


06-30-2005, 06:01 AM
Early-on, when the boat was fairly new, I traced a similar sound under the same conditions you describe to the cutlass bearing. It is the rubber-lined bushing that is held by the strut under the boat, with the shaft in turn running through it.

I was told it was normal, before the cutlass bearing has worn much.

Now, at 360 hours, no more sound while in the water. But am getting a vibration....time to replace the cutlass bearing I'm sure, but that's a pain.

You can perhaps duplicate the sound on the trailer by turning the prop by hand, which is what I did. You might find its the cutlass bearing and not the packing.

07-07-2005, 10:38 PM
You can also check for small areas of polish or wear on the surface of the propeller, same place on each blade. My prop guys noticed them on my OJ for the 99 Mobius. Said it had someting to do with the a bubble stream comming off of the strut. Not sure if that would cause the noise but might be worth looking at.

07-11-2005, 09:21 PM
I'm getting the same sound on my 04 Mobius (170 hours). Has anyone found the root cause? I checked it all out and sprayed a little WD-40 on everything I could see. No impact. I do not think it is anything to really worry about, but I would like to know how to fix it.

07-12-2005, 09:42 PM
I also just started getting this sound and have an 04 Mobius LSV with a 174 hours. I have not yet traced the source. The sound is high pitched and varies in length. I have noticed that is is more common after operating the boat for awhile. It does not happen before the boat is at operating temp for some time.

07-17-2005, 04:24 PM
Just an update. Back from a week at Norris Lake. Happy to report my dealer was correct. First day back in the water I notices it, but it got less frequent and by the end of the week was completely gone. I had timed the drips, and they were a little too far spaced. By the end of the week, they were normal and all sounds gone. Another perfect week of operating for my '02 Mobius.

09-09-2005, 05:37 PM
I get the same sound when I shift into neutral. It is possible I have another problem than the packing gland. I have not had any work down on the packing gland, so I can't figure out how it could be too tight all of a sudden.