Oops
 

I diagnosed a horrendous engine noise as a blown lower unit… WRONG !

Here’s the story…..

bought a brand new OEM lower unit, bolted on,,, same freaken noise…. Grrrrrrr

finally got a Mobil mechanic to stop by, puts the muffs on , starts er up,,, sounds like garbage disposal with silverware in it… increased rpm lessons the noise…
with the engine in the water in gear same horrendous noise..

here’s the punch line,,, he pulls the plastic shroud off that covers the fly wheel and timing belt,,, low and behold the fly wheel nut is sitting on top of the fly wheel at the edge of the wheel…. puts the nut back on torque it down,,, NO MORE FREAKEN NOISE !

5 weeks, $1800 lower unit and countless hrs looking for the cause of that ungodly racket, it’s a loose nut…

best I can figure at low rpm it really jumped around and made the most noise,,, at higher rpm centrifugal force kept it forced out to the edge with less noise… the nut hitting the shroud made one sound and when hitting the fly wheel it resonated down the drive shaft and made it sound like lower unit failure!

I hate to admit it but I’m the yahoo who changed the timing belt a couple yrs ago and evidently didn’t torque the nut enough… Dah!

if nothing else I saved some money not burning any fuel….. for sale: 68V-45300-34-8B lower unit….
__________________
Thanks, Gup
God Bless America

Yikes Ray
Sorry to hear this
Better luck next time
Posted from my iPhone/Mobile device

Lost time is lost time. Bummer...

But you should post up what motor(s) this lower unit will fit. See if we can help you and someone who needs a lower unit...

5 weeks lost for no reason certainly sux
I bet your kickin yourself fornnot digging at it a bit more 5 weeks ago
Oh well
Fixed now!! Go fishin.
Posted from my iPhone/Mobile device

Go get them Ray. I finally decided I’d join the sh*t show out front and splashed the kayak at 4:30 to the most Erie sounds coming front the point. Every rock had one or more seals on it and they were all moaning and singing together, in low light and fog it was spooky. Got four bass over 40” and finally got one slot for a party tomorrow. A humpback surface right next to me and swam under the kayak and a pair fed all morning, luckily all the breeches weren’t that close, but so cool to watch them. I have never in my life seen so many bunker and after the sun broke free of the clouds it got hot, off the water at 9:30.

Can't believe that transmitted all the way down to the LU.
Posted from my iPhone/Mobile device

If someone needs a lower unit pretty easy for them to check out if this one will work for them,,, I’ve got my own problems… LOL

I was with Ray that day maybe because we are both hard of hearing it sounded worse than it was . But I never would have guessed a fly wheel nut could cause that noise and the vibrations in the motor!

Amazing
Posted from my iPhone/Mobile device

Unit will fit Yamaha f115 motors for 2000, 2002-2010, 2012-2013

Every once in awhile you make me happy I sold my boat.....