# Yamaha 90 4 stroke squealing?



## downLOWEdiver

My Yamaha 90 4 stroke outboard starts making a very high pitched squealing sound while at idle speed. It gets very annoying and is even more aggravating because we can't seem to figure out what is causing it! Does any one know what this might be or perhaps how to fix it? I would greatly appreciate the help.


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## DOUBLE "D" & LV

Could be the drive shaft bushing in the midsection. They are brass and rubber. Sometimes they squeal loudly. You can replace it by dropping the lower unit. It will be in the midsection. Might as well replae the water pump while your there. If it is under warranty, they should cover it. One other item that may cause it is the belt tensioner pulley on the powerhead.


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## downLOWEdiver

I have checked the belt tensioner pulley many times, so I think it must be the drive shaft bushings that you mentioned. What would the purpose be in replacing the water pump too though? Do you think that might be contributing to the noise? Or is it for something else?


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## Sequoiha

On some 115s and 150s, i have seen the drive shaft dust seal making a noise,,, a little spray lube will take care of that,, havnt heard it on a 90 yet,,, there is some lube that yamaha makes just for this...


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## DOUBLE "D" & LV

If you determine that you will drop the lower unit, your water pump is there in front of you. Not sure how old or how many hours are on it, but it will save you from dropping the lower unit again to change the waer pump. Just one of those "it's already to that point" repairs that is an options to save labor down the road.


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## downLOWEdiver

Ah, ok. Just one of those "while i am here" repairs. Ok well I will check it out. I really appreciate the feed back on this. That noise is starting to drive me crazy!:banghead


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## outbrdwrench

If the noise is in fact coming from the drive shaft bushing & it is not destroyed, yamaha has a newer grease & procedure for cleaning the bushing & applying the new WR-2 grease. It will shut up that annoying noise, but be sure & listen to Davlor about checking the water pump, he is just tryingto save you money in the long run! outbrdwrench.


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## metal11

That drive shaft seal squel has become such a problem with Yamaha that the do make a special grease to help stop it. How ever if you do use that grease make sure you follow the proper procedures for changing to a different grease. Not all grease are compatable with each other. That is why Yamaha says to clean out all old grease before using the new stuff. Just a something to think about.


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## downLOWEdiver

Thanks for the help everyone, I am making a trip to the dealer today. Now that I know what the problem is, they should be able to take care of it. And I will also replace the water pump while I'm at it. Thanks for the heads up on that! One less thing to worry about later.


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