A Boat’s Capacity Always check the capacity plate usually near the operators position or on the boats transom. This plate indicates the maximum weight capacity or the maximum number of people that the boat can safely carry.

Look for a capacity plate near the operator’s position or on the transom of the boat. This plate indicates the maximum weight capacity and/or the maximum number of people that the boat can carry safely in good weather. You should not exceed either the stated maximum weight capacity or the maximum number of people.

Like a Vehicle Identification Number given to automobiles, the HIN is used to identify each boat. HIN’s are located at the stern of the boat, usually on the starboard side of the transom, or as close to that area as possible. It’s used to register your boat and to track your boat’s history.

Each Capacity Plate includes the maximum number of adult persons, the maximum gross load, and the maximum size of engine, in horsepower, that your boat can legally carry. The next time you’re around a boat, look for its Capacity Plate; it should be permanently fastened near the steering area, or the helm.

If your boat does not have a capacity plate, the U.S. Coast Guard recommends the following formula for calculating maximum occupancy: multiply the boat’s length times its width and divide by 15. For example, a 6-foot wide, 18-foot boat can carry up to seven people safely.

The rule of thumb is based on weight alone, and says you should have between 40 and 25 pounds of weight for each horsepower. For example, a 5,000-pound boat could have an engine with between 125 and 200 horsepower.

The rule of thumb guidelines based on weight alone would be between 40 and 25 pounds of weight per 1 hp. In other words a 5,000 lb boat fully loaded could have a 125 to 200 hp engine. The wide range, based on weight alone, is due to the variety in design and handling characteristics of a given boat.

The most simple way to determine the max safe load your boat can carry is to measure the volume of the immersed portion of the hull, in cubic feet, at the designed max waterline. Multiply that volume by 63 for fresh water or 64 for seawater and deduct the deadweight of the boat.

It’s not a federal violation to exceed the listed capacities, but many states have statutes prohibiting you from exceeding the capacities listed on the plate. That also goes for the outboard. Exceeding the recommended maximum horsepower limit might be illegal in some states.

Putting too many people and gear aboard reduces freeboard, increases instability, and raises the risk of swamping in rough weather. Even in calm waters, an overloaded boat is more likely to capsize, especially if the boat makes an abrupt turn, or if someone on board suddenly shifts position.

“If you overpower the boat, it will not steer as it was tested,” said Tom Brown, an investigator with the U.S. Coast Guard’s Marine Safety Office in Morgan City. “It could possibly turn too quickly and eject the operator or passengers.”

Setting the Outboard Motor Height If the outboard is too low, it creates excessive drag, which cuts into speed and fuel efficiency. If it’s too high, the propeller tends to ventilate, losing its bite on the water and blowing out while turning and in steep seas.

Can I use a bigger motor on my boat than what it’s rated for? It is not a violation of Coast Guard regulations to install or use an engine larger than specified on the capacity label, but there may be state regulations prohibiting it, and restrictions from your own insurance company regarding this.

It seems obvious that the maximum horsepower rating is to keep us from speeding out of control with an oversized engine and, since these ratings are mandated by the U.S. Coast Guard, it’s a logical assumption that these capacities are the result of their testing.

(i) The boat must be rigged with equipment recommended or provided by the boat and motor manufacturer and tested with the highest horsepower production powerplant for which the boat is to be rated, not to exceed 40 horsepower. Boats without permanent tanks must be tested with one full portable tank.

The boat’s capacity plate will list the maximum horsepower for your boat and can usually be found located near to the helm, steering area, and in full view of the captain.

70 horsepower

If your pontoon boat has a 115hp engine, you’ll likely be able to tow tubes or ski even with a full boat. It won’t be as much of fun as with only 4 or 5 people, but you’ll be fine.

The 60hp would be good for a child to waterski and likely “OK” for an adult on two skis….but when someone wants to try slaloming (one ski) it isn’t going to work unless they get up on two skis then drop one. That’s ok, but a PITA when you have to go back and look for ski that has flipped upside down.

50 hp is marginal for lightweight skiers. wakeboarding does not require high torque starts like watersking because you ride the board up like a airplane wing. Waerski tips start with the tips up and you plow the water to a plane. If you plan on a lot of skiing especially slolom you will need a larger boat.

You shouldn’t have any troubles with a 60hp!

A 75 hp motor will pull skiers no problem. The main thing would to have a second prop at least 2 pitchs lower to help give you more power to pull them up.

Horsepower and Speed Tubing doesn’t require quite as much speed, and you can start to have fun at around 15 miles per hour. A pontoon boat with a 70 horsepower engine is plenty for tubing. And 90 HP might be enough for a 20-foot boat to pull a skier, but you’re going to need more engine to ski behind a 26-foot boat.

Your 40 hp 4 stroke will pull some smaller folks on tubes at about 18 mph, maybe 20 mph. If this is fast enough, go for it. Tubing, in general, especially for bigger folks and higher speeds generally take a bit more power. If you could get the 60 hp motor, you would get considerably better performance.

Some 90-hp engines in 18′ aluminum boats with two people aboard will perform almost as well at cruise and have a WOT in the low 40s. 16′ aluminum boats are popular and a 60-hp engine will typically propel them from 25 mph to 30 mph top speed, depending on load.

90HP

A: Although you could pull tubes with just about any size outboard, to be safe you would need at least a 90hp engine to satisfy the tubers in your family. The ideal engine would be a 115hp or 150hp engine if your family is big into water sports.

While a 40 hp engine might be okay to push a pontoon boat around the lake for a leisurely ride, it’s not going to be strong enough to pull most skiers. This size motor will give you plenty of speed for towing tubes, as well as pulling most skiers and wakeboarders too.

When towing young kids on tubes, keep the speed between 8 and 12 MPH. The younger the age, the slower the speed. When towing teenagers/adults on tubes, keep the speed from 15 to 20 MPH.