1997 Yamaha 150 Noise At Certain RPM

[jasonalden]

I recently purchased a boat with a 1997 Yamaha 150 Saltwater Series engine.<br /><br />After getting acquainted with the boat, I noticed that at 3700-3900 RPM the engine is much louder than higher or lower RPMs. The sound is hard to explain; it just sounds like it is working it's hardest in that range.<br /><br />Is this common & expected or might I have a problem?<br /><br />Thank you,<br />JA<br /> http://thealdens.org/boat

 

[Osprey]

Re: 1997 Yamaha 150 Noise At Certain RPM

Depending on the size/weight of your boat, you may need to try another prop.

 

[Ray Neudecker]

Re: 1997 Yamaha 150 Noise At Certain RPM

This is a fairly common thing. It has to do with the timing and fuel advance curve of the engine. Personally I avoid running at those RPM's where reasonable.

 

[jasonalden]

Re: 1997 Yamaha 150 Noise At Certain RPM

Thanks!

 

[jasonalden]

Re: 1997 Yamaha 150 Noise At Certain RPM

Thanks!<br /><br />JA<br /> http://thealdens.org/boat