75 merc sqeaking/squealing noise

[azzclwn]

I've got a situation with my 2000 75 merc 2 stroke.

After the motor is run at heavy load (ie wide open) for a period of 5-10 minutes, when I throttle down to troll there is a loud squeaking/squealing noise when the boat is in gear and in neutral. However, if I don't run the thing wide open I can troll with it all day and not hear the noise. It's after I push it a little harder the the noise pops up.

The motor is pushing a alumacraft Mag 165 CS, I fog the motor every fall and change the lower unit oil. The pee stream has always been fine as well.

I changed the plugs and fuel filter last year.

Any ideas where to start?

[azzclwn]

bump...

anyone have any ideas,

I sprayed the shaft with silicone in an attempt to loosen up the bushing,

seemed to help for a little while,,,, noise returned this weekend and seemed worse.

Any thoughts???

[Valv]

Sounds very weird. Is that avatar from Brokeback Mountain ?

[HaywardBound]

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Is that avatar from Brokeback Mountain ?

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So, you have seen the movie?

[Valv]

No thanks, to me it's a shame they even made a movie like that.

[azzclwn]

Sounds very weird.

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Is that avatar from Brokeback Mountain ?

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yep, i thought it was kinda funny, in a sarcastic sorta way.

guess i have a weird sense of humor, any ideas on my mysterious noise?

[Surface Tension]

Is it a constant squeal or a a chirp, chirp?

If it metal on metal or a bearing you could be doing damage by running it. I should say more damage then then just a bad part that could result in a damaging something else.

Having said that you'll need to find out whats going on. You can do that yourself or bring it to a dealer.

Next time this happens put the boat in neutral and put your weight on the outboards cover and try and stabilize the outboard. What I'm getting at here is the squeak could be just rubber bushing.

A 1/2" vinyl hose put to the ear with the other end searching for noise is a good way to detect where the noise is coming from. Do that around the carbs and engine, Theres a bearing on the drive shaft just below the water pump/impeller housing that could be bad also.

Let us know what you find out.

[azzclwn]

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Is it a constant squeal or a a chirp, chirp?

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sounds like a slipping fanbelt, obviously the motor has no belts. I only hear the noise after I run it hard for a period of time, then as I'm idling through a no wake for instance it'll squeak for 5 minutes and then quit.

I think it's heat related because, my last time out, on purpose I ran the motor upriver for about 15 minutes at 4000 RPM, slowed down up at the dock, no squeal.

If I had run wide open(5200 rpm) for that period of time it would make the squeal noise for sure. I think it's heat related based on fact that it didn't do it after running at the lower RPM(less heat)

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Having said that you'll need to find out whats going on. You can do that yourself or bring it to a dealer.

Next time this happens put the boat in neutral and put your weight on the outboards cover and try and stabilize the outboard. What I'm getting at here is the squeak could be just rubber bushing.

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Never thought of that I'll give it a try

I haven't ever changed the impeller, maybe I'll start there, is the impeller difficult to change?

If that doesn't work she's goin to the shop.

Thanks for the ideas.