Yamaha 70 Lower Unit "chatter"

[jcminnesota]

HI all. I just got back from the MN boat show and talked to Yamaha reps about the new 70. They said there have been some complaints about lower unit "chatter" at idle speed that have prompted some complaints. They assured me that its not a functional problem but that some folks found the "chatter" irritating. They also said they were working on a fix and that was to develop a prop with a softer shock absorber. Has anyone experienced this? Is it really irritating? Does it affect trolling speed? I am in the process of buying an Alumacraft Classic 165 with a new Yam 70 and am a bit gun shy after hearing this...

 

[Capt Ken]

Re: Yamaha 70 Lower Unit "chatter"

They had the same problem with some of their larger engines but solved the problem with a different hub in the prop. It's more noticeable at idle and goes away once you throttle up. Most buyers never notice the noise.

 

[jcminnesota]

Re: Yamaha 70 Lower Unit "chatter"

Thanks Ken.....they said they would also have newly designed prop for the 70 within the next year with a different hub that would eliminate the "chatter" but they also confirmed that most buyers don't notice it. And I am coming from a 1986 70 Yamaha 2 cycle. They said for me it would seem much quieter than my old 2 cycle. They did say that with the larger diameter prop that it may not be slow enough for trolling however.......do you have an opinion on that? In the northland for walleye 1.0-1.5 mph is good. 1.5-2.5 for Northern Pike and Muskie.

 

[Capt Ken]

Re: Yamaha 70 Lower Unit "chatter"

I've seen northern boats with those trolling things that drop down behind the prop and reduce the trolling speed. Don't know what they are called. Some Yankee invention.

 

[TwoFish]

Re: Yamaha 70 Lower Unit "chatter"

mine chatters quite badly at idle. Need to get up to about a thousand revs to smooth out. It is possible to idle smoothly at times but if it starts chattering you need to increase revs. Other than that its a great motor.