90hp motor whine (low rpm)

[thunderjet]

I have a 2007 yamaha 90hp 4 stroke. Bought the boat last year (new) and now has approx 50 hrs on it. The problem is when I idle down and travel at low speeds it makes a high pitch whine. It will stay that way untill I speed up. The pump seems fine and and so does the fly-wheel belt, there was a slight rubbing on the cover. I had a mechanic check it out but he didn't know what it was. This has done this since new. Does anyone know what it might be ?

 

[Island Fish Lifter]

Possible the electric fuel pump...

Fill the dam tub!

 

[Island Fish Lifter]

Possible the electric fuel pump...

Fill the dam tub!

 

[SeaWolf]

http://www.thehulltruth.com/shipyard-isl-marine-engine-parts/182278-f115-making-strange-noise.html

 

[Sea Ranger]

Hi thunderjet,
I don't know what your noise is but back two years ago I had a motor(50 hp 2 stroke) that had a death rattle as I was told and the noise use to come and go.... long story short.... I found out it was a loose bearing and it caused the piston to come up a bit too far and the piston hit the top of the head and it never made another noise again. Never ran again either...probably nothing like yours but any noise could be a problem.

And remember....Keep your tip up!!!

 

[thunderjet]

quote:Originally posted by thunderjet

I have a 2007 yamaha 90hp 4 stroke. Bought the boat last year (new) and now has approx 50 hrs on it. The problem is when I idle down and travel at low speeds it makes a high pitch whine. It will stay that way untill I speed up. The pump seems fine and and so does the fly-wheel belt, there was a slight rubbing on the cover. I had a mechanic check it out but he didn't know what it was. This has done this since new. Does anyone know what it might be ?

What a great site,and the info from the guys are great. I hope I can solve this problem,it sounds like one of Yamahas defects maybe the spline shaft bushing. I will have a mechanic check this out,as it seems lots of people are having this problem at low rpms.

 

[clearwaterB]

I had a similar problem on my Merc125 jet, it turned out to be a bad starter. it was staying on, but not going up and engaging the flywheel. The bendix (not sure of spelling) was shot

 

[Charlie]

Welcome to the world of Yamaha!

I actually have 2 225s and they take turns whining, but only at an idle. They have been doing it ever since I have owned the boat. I have had them checked several times and no one has found any problems with either!

IFL, is probably right about the fuel pump! techs have written it off as the fuel pumps!

 

[Charter Tofino]

Had the same thing happen here and there on my 2005 90hp 4strk merc. Its most often when i start it up and its cold. Havent heard it this year though so maybe it just needs to be worked in. Im just happy that its a merc and still running

 

[Gunsmith]

My theory is that most marine engines whine as they go by a fuel stop.

 

[Charlie]

 

[Tsquared]

quote:My theory is that most marine engines whine as they go by a fuel stop

You're wrong on that one, Gunsmith. The most persistent whine is the spousal whine when they read the fuel bill on the credit card statement.
T2

No Rigours

 

[Gunsmith]

HaHa I have to agree with that one! Also that gives them crowsfeet when they see the bill. Mine left me 16 yrs ago so I have to whine by myself!!