strange sound traveling through my boat hull

[Stingray606zp]

Boat is a 1996 stingray 606zp. 4.3 vortec, alpha1 generation 2 out drive. Ill give a little history. I bought the boat late last season. I redone the back seat and storage area because one corner was soft. I used all the original hardware in the same spots, just changed the wood. The next outing was when i first noticed the sound. Now, im not sure if the sound just showed up that time, or if i just hadnt realized it until then.

I took it out yesterday for the first time this season. The sound traveling through the hull is at low rpms. Its most noticeable between idle and 1200rpms. Does it anytime the engine is running. Sound doesnt change in forward or reverse. Trim up, trim down, full left or full right it doesnt change a bit.

So here's where i am. Should i pull the drive and have a look at the gimbal bearing and u joints, or look for something else first? I dont know if i done something to make sound travel when i redone the back seat and storage area, or if something else is going on. The sound is just kinda like harmonics traveling through the hull.....kinda like a real small vibration that the sound is traveling through the fiberglass hull.

I hope i put this in the right forum, this one seemed most fitting .

 

[Don S]

Re: strange sound traveling through my boat hull

So here's where i am. Should i pull the drive and have a look at the gimbal bearing and u joints,

Absolutely.

 

[Silvertip]

Re: strange sound traveling through my boat hull

Remove the back seat and see if that changes or eliminates the noise. Gone = problem is seat induces. Not gone = something else in the engine/drive.

 

[Stingray606zp]

Re: strange sound traveling through my boat hull

Knowing my luck I figured it would be the worst, So I pulled the outdrive first. Easier than expected!! I believe the bearing is probably the problem. The grease was nice and clean best I could tell, but the bearing felt a little ''gritty'' in a few spots while turning it,,,kinda like sand in it or something. They was just a very little bit of brown water in 1 of the grooves of the bellow closest to the bearing, you can see it in one of the pictures. The bearing is a Link Belt brand, no idea if it's original or not.

Unless I'm missing something on the U-joints, They feel and look great. They's no grease fittings to grease. The rubbers are soft and pliable, makes me wonder if they haven't been changed before.....

Anything else I should do as a preventive maintenance while I'm in there? How about the bellows? They appear to be in decent shape, very little cracking in the corners,,, I might need to post a picture of them too for an opinion. I also wonder about that little puddle of water in there. The boat was on the water 5 hours yesterday, but that brown water looked like it had been in there awhile, I guess I really don't know for sure though.

Any input appreciated

 

[Don S]

Re: strange sound traveling through my boat hull

but the bearing felt a little ''gritty'' in a few spots while turning it

That's what makes the noise. Time for a new gimbal bearing, and make sure the alignment is ok before you pull the old bearing.

 

[Stingray606zp]

Re: strange sound traveling through my boat hull

Besides a bearing puller, Alignment tool, and bearing install tool, Is they're any other special tools I will need?

 

[Don S]

Re: strange sound traveling through my boat hull

Besides a bearing puller, Alignment tool, and bearing install tool, Is they're any other special tools I will need?

That should do it.
A big slide hammer works for pulling the bearing. Don't really need anything special.

 

[Stingray606zp]

Re: strange sound traveling through my boat hull

Thanks! I got a gimbal bearing kit complete with gasket and seals coming. I also went ahead and got all the tools to do a bearing and bellows change. I could have probably had the bearing changed for cheaper, but now I got the tools to do it again if/when the time comes. Also got several boating buds that the tools may be beneficial to one day so I'm sure It'll pay off....plus if I do it myself I know it'll be right .

I replaced the impeller 2 weekends ago, I should have pulled the drive and checked the bearing while I had the lower off....but I wanted to be sure of the noise again. I Think I'll make checking gimbal bearing and bellows part of my winterizing list....I'll know a little more about boats this year though lol....and I'll have all winter to work on it. Hopefully I'll get this bearing changed one evening this week and get to try it out next weekend.

 

[Don S]

Re: strange sound traveling through my boat hull

Read the winterizing and summerizing threads in the link below. The stickies.
------------ADULTs ONLY -------------------------No Exceptions-----?/ 288430

 

[Stingray606zp]

Re: strange sound traveling through my boat hull

Thanks Don! I found it last year and read it, but I was already winterized and put away for the year. I'll follow it this year, I like the idea of doing that stuff in the fall of the year before It's stored. I did get everything winterized well though. I'll do better this year now that I'm here .

 

[Stingray606zp]

Re: strange sound traveling through my boat hull

she's fixed . Got it back together friday evening, test drive today.....quite as a button. Thanks men!