Yamaha Marine Group said its call center history suggests a significant number of outboard-powered boats may have a prop that is not offering the best performance because of an often forgotten factor: actual load. Meaning, some customers’ boats are not delivering peak performance or fuel efficiency, an issue that can be remedied by specifying a new propeller.
“Our customer service representatives and technical service representatives deal with performance and fuel consumption issues on a daily basis, and we most frequently trace them back to customers not having a prop that offers peak performance for the kind of boating they do,” said Steve Friedrich, Yamaha Marine Group technical service manager.
“Choices in propeller specifications – pitch, diameter, blade shape, etc., are most often based upon best predictions of how customers will use their boats. In everyday use, however, boats often carry much more load than even the boat owner imagined. Passengers, gear and a full tank of fuel add weight, and weight changes the characteristics of the boat. The best way to ensure economy and performance is to prop the boat for the normal load and boating conditions. “
The first step in choosing the right prop is to determine how the boat will be used. How many passengers? How many coolers? How much gear? How many skiers? Calculate the weight of the passengers and gear, and then make sure your boat dealer uses this figure to help identify the appropriate prop for the boat.
The second step is to test the prop choice under the actual loaded conditions. If passengers and gear are not available, add ballast to the boat that equals the weight of the expected load.
Finally, with the boat loaded, check to be sure the outboard can reach its maximum rpm without exceeding it at full throttle. If the boat does not reach maximum rpm or if it exceeds it and engages the engine’s automatic rev limiter, the propeller choice is not optimal for the boat and may not deliver optimal fuel consumption.
If peak rpm is consistent with wide-open throttle operation in this test, the boat will also deliver the best performance and fuel consumption all through the rpm range, even at cruise, so long as the load conditions remain consistent.
Yamaha Marine products are marketed throughout the United States and around the world. Yamaha Marine Group, based in Kennesaw, Ga., supports its 2,200 U.S. dealers and OEM partners with marketing, training and parts for Yamaha’s full line of products and strives to be the industry leader in reliability, technology and customer service. Yamaha Marine is the only outboard brand to have earned NMMA®’s C.S.I. Customer Satisfaction Index award every year since its inception. Visit
This document contains many of Yamaha’s valuable trademarks. It may also contain trademarks belonging to other companies. Any references to other companies or their products are for identification purposes only, and are not intended to be an endorsement.By: Martin Peters, Mgr Communications
