Please select your home edition
Edition
Pantaenius PWR Asset 728x90

Boaters aren’t the only ones getting heavier: Outboard engines catch up

by Scott Croft 31 May 16:16 UTC

One year ago the U.S. Coast Guard required new recreational boats to have more floatation to support the increased weight of newer four-stroke outboards if the boat becomes swamped.

Now the agency is implementing those changes as reported in the Spring 2019 issue of the U.S. Coast Guard Boating Safety Circular. Boat Owners Association of The United States (BoatUS) advises recreational boaters to be aware of this issue when considering repowering an older model year vessel with a heavier four-stroke outboard.

"Repowering with a newer, more reliable, cleaner, fuel-sipping outboard is one way to get more life out of a good boat," said BoatUS Foundation president Chris Edmonston. "However, after having gone through the recent repowering of a 22-foot center-console vessel with a heavier four-stroke, and seeing first-hand the resulting loss of freeboard and performance, we want to remind owners to consider engine weight. With a potentially heavier four-stroke motor and resulting lower freeboard at the stern, swamping is a concern and your boat may handle differently than with the old engine."

If you don't know the weight of the engine you're replacing, Edmonston recommends you contact the manufacturer before you repower. A boat dealer or repair facility may also be able to provide that information to ensure that, regardless of horsepower, the engine weights are similar.

Federal requirements mandate that outboard-powered monohull boats 20-feet and under must be built with enough flotation to keep the passenger-carrying area at or just below the water's surface in the event of swamping or capsizing. The boat must float level. There are no floatation regulations for vessels over 20-feet long.

When these regulations were written in the early 1970s, virtually all outboards suitable for smaller boats were two-stroke models covering a broad range of horsepower, but that's no longer the case. Four-strokes come in virtually every size now, making them viable candidates for installation on more boats. While recently there have been some two- and four-stroke models with comparable power and weight, by and large four-stroke outboard engines remain heavier. A four-stroke's more complex valve systems typically add 10% to 15% or more weight than their two-stroke counterparts. Twin engine installations compound the weight problem.

This isn't the first time the Coast Guard has recognized a growing vessel weight issue and updated regulations. In 2011, the "Assumed Average Weight Per Person" was increased from 140 to 185 lbs., but only for commercial passenger vessels. Existing formulas for weight capacity on recreational boats were considered adequate and did not change.

Related Articles

Boaters urged to weigh in on Erie Canal future
Community engagement sessions this week; share comments online The nation's largest advocacy group for recreational boaters, BoatUS is urging Empire State boaters and those who transit the Erie Canal System to have their voices heard at upcoming "Reimagine the Canal" stakeholder sessions this week. Posted on 16 Jul
Affordable 3-hour on-water training courses
Lake Norman, North Carolina, to host Coming to Lake Norman are two fun and affordable on-water boat training courses taught aboard single-engine powerboats: Intro to Boating and Women Making Waves. Posted on 15 Jul
Affordable 3-hour on-water training courses
Want to learn the basics of powerboating or brush up on your skills? The nonprofit BoatUS Foundation for Boating Safety and Clean Water together with Freedom Boat Club Yarmouth offer a choice of two fun on-water boat training courses taught aboard single-engine powerboats: Intro to Boating and Women Making Waves Posted on 6 Jul
Florida Governor signs Recreational Boat Title Act
What it means to boaters both inside and outside the Sunshine State Florida Governor Ron DeSantis' recent signing of a recreational boat title bill, the Uniform Certificate of Title Act (HB 475/S 676), offers recreational boat owners valuable consumer protections and may spur other states to follow suit. Posted on 3 Jul
The secret to surviving July 4th on the water
Possible mayhem at launch ramps, marinas and popular anchorages Each year about three out of four recreational boat owners say they plan to enjoy the Fourth of July holiday aboard the family boat. With nearly 12 million registered vessels in the U.S., that could spell mayhem at launch ramps, marinas Posted on 28 Jun
Boaters beware: Expect more E15 this summer
A bad fuel is lurking Over the objections of a wide coalition of American citizens and environmental, conservation, food producer, fuel retailer, taxpayer advocate, and outdoor recreation industry groups, the Environmental Protection Agency (EPA) Posted on 18 Jun
Affordable 3-hour on-water training courses
Intro to Boating and Women Making Waves offered on Lake Norman The nonprofit BoatUS Foundation for Boating Safety and Clean Water together with Freedom Boat Club Lake Norman offer a choice of two fun on-water boat training courses taught aboard single-engine powerboats: Intro to Boating and Women Making Waves. Posted on 1 Jun
6 ways boaters can be green this summer
All across America boating season has begun. With some help from the BoatUS Foundation for Boating Safety and Clean Water, here are six ways boaters can help keep waters clean and be good environmental stewards all summer long. Posted on 29 May
BoatUS releases annual list of Top 10 Boat Names
The tradition dates back a quarter century Each year, Boat Owners Association of The United States (BoatUS) tallies the most popular boat names. The tradition dates back a quarter century, with the list derived from adding up requests for boat name designs from BoatUS Boat Graphics. Posted on 24 May
New on-water boat towing service opens
Professional 24-hour on-water assistance for Lake Cumberland Rich Lenardson used to be in the vehicle recovery business, on the highways at all hours of the day and night. But in 2007, he took to the water and opened his first TowBoatUS 24-hour on-water boater assistance service on Lake Michigan. Posted on 24 May
BandG AUS Zeus3 FOOTERRaymarine AUS Lighthouse 3 Annapolis 3.9 - BOTTOMGJW Direct - Motor Cruiser 2019 - Footer