Strange noise from Sterndrive

Robertpel9

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Apr 20, 2008
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265
Not sure if this is even an issue or not but please let me know if you have any insight into this.

I have a 1995 Chris Craft with a Volvo 4.3GS with SX drive and a hustler vented aluminum prop. Boat runs perfect and could not be happier with it. There is a for lack of a better way to put it whistling noise that i get when I have the engine trimmed out about a third of the way up the gauge. Any less trim than that and it goes away, any more than that and it goes away as well. It also will go up and down in pitch (the noise goes up and down in pitch) with the waves at times. I wish i could describe it better but that is the best way i can articulate it. Engine is the original 1995 Volvo with 109 hours on it and the drive

There is no performance issues, handling issues, etc. I just would like to know what the cause could be as to be honest at the loudest point it is somewhat irritating. Also I want to make sure i am not sitting on some sort of major time bomb waiting to happen. It is not a grinding noise it is a whistle or whine so to speak and the trim position is what does it not turning or anything else you would associate with a Gimbal, etc

I talked with the used dealer i bought it from a few months and 20 engine hours ago and he is confident it is just harmonic noise due to it being only at one trim level (goes away at all others) and looking at everything before we put it in the water. He assured me that everything was serviced right before sale and I should not worry at all. I am suspicious but who knows

Like i said all other levels of trim it is non existent - what could it be. The bad part is the same level of trim where it occurs is also the "best" level of trim for my boat in most water conditions at cruising speeds.

Thanks for any input,
Robert
 

tashasdaddy

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51,019
Re: Strange noise from Sterndrive

when was the last time the drive has been off and serviced. including gimbal bearing etc.
 

Robertpel9

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Apr 20, 2008
Messages
265
Re: Strange noise from Sterndrive

when was the last time the drive has been off and serviced. including gimbal bearing etc.

Never, was winterized yearly and greased, oil change, lube change, etc but was a 1 owner who rarely used it (89 hours on a 1995)
 

12vMan

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Jun 4, 2008
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1,536
Re: Strange noise from Sterndrive

Gimbal Bearing would be my best guess
 

12vMan

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Re: Strange noise from Sterndrive

Also, if it is indeed the gimbal bearing, best to have a complest outdrive service performed. The used boat dealer most likely just did a fluid change at best, and maybe an impeller
 

tashasdaddy

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Re: Strange noise from Sterndrive

an inboard outboard, requires a lot more maintenance than an outboard. get the outdrive pulled and complete service. before you ruin it.
 

bomar76

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Jun 27, 2002
Messages
1,963
Re: Strange noise from Sterndrive

Never, was winterized yearly and greased, oil change, lube change, etc but was a 1 owner who rarely used it (89 hours on a 1995)

That makes it 8 years overdue.
Pulling the drive is a yearly (normally at witerization) occasion.
 

Robertpel9

Petty Officer 1st Class
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Apr 20, 2008
Messages
265
Re: Strange noise from Sterndrive

an inboard outboard, requires a lot more maintenance than an outboard. get the outdrive pulled and complete service. before you ruin it.

The impeller was changed two months ago.

What exactly is a complete service (What specific procedures does it entail) and what is a range that i should expect to pay to have it done at the marina??

How often is this complete service needed. If it is yearly then what is the point of looking for such a low hour boat. Guess ia m still learning.

Any chance this noise is just a normal sound at that particular trim level and everything is fine?
 

180shabah

Rear Admiral
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Mar 26, 2005
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4,995
Re: Strange noise from Sterndrive

[size=+2]an inboard outboard, requires a lot more maintenance than an outboard. get the outdrive pulled and complete service. before you ruin it.[/size]
 

12vMan

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Re: Strange noise from Sterndrive

The impeller was changed two months ago.

What exactly is a complete service (What specific procedures does it entail) and what is a range that i should expect to pay to have it done at the marina??

How often is this complete service needed. If it is yearly then what is the point of looking for such a low hour boat. Guess ia m still learning.

Any chance this noise is just a normal sound at that particular trim level and everything is fine?

The simple fact that the boat is a 95 means it could need several things replaced that wear by just sitting.

You need to take it to a qualified mechanic to go over everything with you. You can expect to pay upwards of $700 on this one. Yearly maintainence isn't this bad, but you need a once-over. I'm sure you can get a free estimate, and if you're not satisfied take it to another mechanic.
 

Gary H NC

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Dec 1, 2005
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8,972
Re: Strange noise from Sterndrive

Robert, The drive should be pulled yearly to inspect the u-joints and gimble bearing.The only way to grease the u-joints is with the drive removed.
If the bellows and everything is all original they are way overdue to be replaced also.
I would ask the dealer you bought it from if the drive was actually removed or just a gear lube change was done.
 

tashasdaddy

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Re: Strange noise from Sterndrive

even with low hours, the bellows are rubber, dried out, due to crack. they are the only thing keeping you from sinking. a bilge pump will not keep up with the water coming in. also water get into important parts of the outdrive. you need to have the drive bearing, checked and aligned every year. you have a great power plant and drive system, if it is maintained properly. if not it will get really expensive, to repair.

also the rubber boots on the exhaust, could be bad, cracked, this would cause cooling water to get into the hull. no a pretty sight watching the water pump, pump water into the boat.
 
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