High pitched wine

(psudy) · (psudy) **Join Date: Dec 2003** 08-03-2006, 7:58 AM

Well this might not be the best place to ask an engine question about an I/0, but here it goes. Last weekend when we were cruising the boat, we noticed a high pitched whine. At first I thought it was the fuel pumps, but when I turned the boat off and turned the keys to the alt position, we didn't here it. Does anyone have any idea what this could be?

(Message edited by psudy on August 03, 2006)

(anodyne) · (anodyne) **Join Date: Feb 2006** 08-03-2006, 8:00 AM

high pitched wine? Never heard of it... Is that a red or a white?

(psudy) · (psudy) **Join Date: Dec 2003** 08-03-2006, 8:10 AM

....and thats what I get for typing fast.

(acurtis_ttu) · (acurtis_ttu) **Join Date: May 2004** 08-03-2006, 8:16 AM

do you have a HO alt? could be that? or your alt coudl be going out (bearings) It could also be the sound of air being sucked into the motor.

(psudy) · (psudy) **Join Date: Dec 2003** 08-03-2006, 8:23 AM

I don't think its air being sucked in. I didn't hear it at all when we test drove the boat a few weeks ago. The alt sounds like a possibility. I will check that.

(anodyne) · (anodyne) **Join Date: Feb 2006** 08-03-2006, 8:24 AM

...I had to Paul

. was it just at a certain speed, or was the whine present throughout various speeds? I know my carbuerator/filter whines in the lower RPM band... just as the engine's getting up-and-going

thug_hunter 08-03-2006, 8:33 AM

I second the alternator as being the likely problem.

You didn't mention it so I'll ask. Have you recently installed a stereo? Is the sound coming from your speakers by chance. If so, it'll be a bad ground.

(psudy) · (psudy) **Join Date: Dec 2003** 08-03-2006, 8:57 AM

No, it has nothing to do with the stereo. It is really loud sitting in neutral, or at idle. Once you get going, you can't really hear it, but I am sure it is still there.

(clubmyke) · (clubmyke) **Join Date: Aug 2004** 08-03-2006, 11:35 AM

have you recently repaired your prop ?

(psudy) · (psudy) **Join Date: Dec 2003** 08-03-2006, 11:41 AM

No. As I said, it is the most annoying sitting in Neutral.

(rodmcinnis) · (rodmcinnis) **Join Date: Sep 2002** 08-03-2006, 1:11 PM

Paul wrote:
"At first I thought it was the fuel pumps, but when I turned the boat off and turned the keys to the alt position, we didn't here it."

So how does that eliminate the fuel pumps? I wouldn't expect the fuel pump (do you have more than one???) to run in the alt position at all and only for a few seconds in the normal ON position if the engine wasn't running.

You can sometimes get a pretty good whistle whine going from the air intake system.

A bearing, from the alternator or water pumps could make noise.

It is possible that it is coming from the transmission, as there are components that are turning even in neutral.

My first guess would be the air intake system.

(dhands88) · (dhands88) **Join Date: Jul 2006** 08-03-2006, 2:17 PM

my guess is the fuel pump whining cause you $2.00 fuel filter hasnt been changed cause your fuel pump to burn up.

(elleduke) · (elleduke) **Join Date: Aug 2005** 08-03-2006, 3:18 PM

I have this same whine on my Indmar TBI 310hp engine. It comes and goes and I think it is the alternator bearings or something that is alternator related that is going out. It comes and goes depending if I have been running my stereo, ballast, lights etc., but if I shut everything down and let it charge everything up it goes away. And no it is not ground interference since the whine does not increase or decrease with the throttle. I am going to up grade from the 70amp to the 90 amp or higher after the season. I have never had a dead battery so I know it is working.

(psudy) · (psudy) **Join Date: Dec 2003** 08-04-2006, 6:47 AM

Rod, the reason I didn't suspect the pump is because I was told that it would run for a minute in the alt position, and we never heard anything.

Danny, I just bought the boat, so I don't actually know for sure how often it was changed(I couldn't quite tell, but I think that is what you were getting at.