150yamaha 4stroke making noise

[Seaswirl10]

I have twin f150 4 strokes 247 hrs last trip one engine started making a noise when I brought it back to idle after a 2hr run at 4500 rpm just a low pitched whine not all that loud i revved it up and it stopped but it come back again .i was at the ramp so I put it on the trailer.does anyone have an idea what it might be. I owned a225 Suzuki done the same thing had to grease drive shaft bushes to fix it

[BaileysBoat]

Squeak might be drive shaft bushing, whirring probably balancer assembly going bad;

Yamaha F150 outboard - with balancer noise - YouTube

[Seaswirl10]

Engine noise

Thanks for that .listened to engine on YouTube definitely doesn't sound like that hopefully its just needs a bit of good quality grease on drive shaft has been 100 hrs since I dropped the gearbox to do the waterpump

[captain rednut]

its service time. grease the driveshaft.
cheers jim

[Seaswirl10]

Noisy engine

Rang mechanic this Arvo all organized for after Easter

[sachin2021]

My F150 has a date of manufacture stating October 2006. Should I be concerned about balancer failure. Motor has done 920 hours.

[TownsendsFJR1300]

My F150 has a date of manufacture stating October 2006. Should I be concerned about balancer failure. Motor has done 920 hours.

My service guy mentioned Yamaha has updated the balancer at least 4 times since 2005. He also stated it'd sound like a washer machine going bad when it goes however even when it starts making noise, you have time to replace it. Its a couple hour job to replace it

I saw a replaced unit, it's extremly heavy duty and looks like it has a heavy duty crankshaft and real thick gears in it... The case is extremly thick as well...

As for the noise, when my driveshaft (with the extension inbetween the ower unit and mid section) was dry (I used the wrong grease) it squeeked at about 1800 RPM and sounded like birds kinda far in the back round chirping. There is a waterproof specific grease that works like a charm.. From experiance, don't use marine, waterproof wheel bearing grease, it will not last...