350 Yamaha outboards

Grady fun 5

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Looking for opinions from anyone who owns or has owned the 350 hp Yamahas from 2011 and forward, other than the flywheel problem that Yamaha takes care of for the life of the motor. Are they good reliable motors
 

mhff34

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There has been a ton of bad reviews on this motor The Gulfstream i purchased had a 350 factory installed i purchased it used with repower. Evidently the previous owner killed 350 with less than 150 hours
 

Grady fun 5

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There has been a ton of bad reviews on this motor The Gulfstream i purchased had a 350 factory installed i purchased it used with repower. Evidently the previous owner killed 350 with less than 150 hours
I have 2 on my 305 and I take it 80 miles offshore on a regular basis the flywheels and ECM were changed in 2017 and I never have a problem. I hope mine are the 2nd generation and they last a wile
. Thanks for your reply
 

eppem

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I can't comment good or bad as I do not own a boat with them but I also heard they are very thirsty.
 

magicalbill

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Grady fun 5:

Read my post entitled "The Latest On Yam 350's."

I have no firsthand experience with prior models, but my 2018's have been great. So far, flawless after 240 hrs. The flywheel change is no big deal, I've had two swapped out already, free of charge as per Yamaha's agreement.
 

Grady fun 5

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I can't comment good or bad as I do not own a boat with them but I also heard they are very thirsty.
It’s true they like to drink fuel but if you really take time and trim the boat for the sea conditions you can get 1.2 mpg but it takes practice. I’m mainly interested if anyone has continued problems other than the flywheels. I don’t mind that because Yamaha will replace them for life if you do all your scheduled maintenance. There huge powerful motors on. Heavy boats and I quess you should be prepared for high fuel consumption. I believe they are going to last many hrs if your experienced with how they need to be taken care of run. I just don’t know of any other problems with them and I’m trying to find other owners for in sight
 

Grady fun 5

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Grady fun 5:

Read my post entitled "The Latest On Yam 350's."

I have no firsthand experience with prior models, but my 2018's have been great. So far, flawless after 240 hrs. The flywheel change is no big deal, I've had two swapped out already, free of charge as per Yamaha's agreement.
That’s great to hear. I also have nothing but good except the flywheels and as you said it’s no big deal. I’m at 360hrs and hope to hear more posts like yours. Thanks
 
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mr_mbuna

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It’s true they like to drink fuel but if you really take time and trim the boat for the sea conditions you can get 1.2 mpg but it takes practice. I’m mainly interested if anyone has continued problems other than the flywheels.
I bought a 2011 Freedom 275 with an F350 on it recently. At 750 hours, the engine passed a mechanical inspection and compression test fine with ~5% variation between the highest and lowest readings (a healthy engine has 10% or less variation). It hasn't given me any trouble.

The factory performance test for a 275 with a single 350 appears below.

275 performance test single Yamaha F-350.PNG

My experience with a hardtop and isinglass is:

5700 rpm - 33.3 gph - 45.0 mph - 1.4 mpg (WOT)
4900 rpm - 20.4 gph - 37.4 mph - 1.8 mpg
4300 rpm - 14.3 gph - 31.8 mph - 2.2 mpg (cruise, for me)

I cruise at 4300 rpm to stay just above the range where flywheel degradation happens even though 3700 would be better from an efficiency perspective. Fuel consumption climbs noticeably above 4000 RPM and then it really ramps up above 5000 RPM. The nice thing is that these torquey engines can be run at a slower RPM than V6 competitors.

Of course you will burn more fuel pushing a 305.
 
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