Parking A Twin-Engine Boat: Tips And Tricks

Parking a boat with two engines can be a daunting task, especially for those new to boating. While it may seem more complex than a single-engine boat, understanding the basics of operating and docking a dual-engine boat can make the process smoother. It is generally recommended to use both engines simultaneously for better control and efficiency. However, there are specific techniques and considerations to keep in mind when parking this type of boat, and it's always a good idea to seek further guidance from experienced boaters or professionals.

Running both engines at once

By running both engines, you avoid the issue of drag caused by the unused motor, which can cause the boat to pull to one side and make steering more challenging. It's important to note that this challenge in steering can be a safety concern, especially for larger boats that can cause significant damage in the event of a collision.

Additionally, running both engines helps maintain more balanced engine hours between the two motors. This is beneficial for service and maintenance purposes, as well as for resale value, as potential buyers may be concerned if one engine has significantly more hours than the other.

However, it's worth mentioning that there may be scenarios where running a single engine is acceptable, such as when idling or moving at very slow speeds. In these cases, it's generally recommended to not push the single engine too hard and to alternate between the two engines to maintain balanced usage.

Steering with one engine

If your boat has twin engines, you can steer it with just one engine. This is because the direction of the boat is changed by adjusting the steering system, which turns the drive unit, and not by the power of the engine itself.

Outboard engines, for example, are mounted on the transom of the boat and power and steer the boat using a tiller on smaller engines or the steering system on larger boats. The steering system turns the entire motor, thus changing the direction of the boat.

Inboard engines, on the other hand, have the engine mounted in the hull forward of the stern of the boat. The propeller is underneath the boat, and a rudder is mounted to the transom and controlled by the steering system to change direction.

Stern-drive engines are similar to inboard engines, with the engine mounted in the hull, but the drive unit and propeller are mounted to the transom. The steering system turns the drive unit to change direction, much like an outboard engine.

So, while having two engines can provide more power and redundancy in the event of a failure, it is not necessary for steering, as the direction of the boat is controlled by the steering system and not the engines themselves.

Cooling systems for each engine

Marine engines require cooling systems to prevent overheating. Boat engines, unlike car motors, use cool water from below the vessel to keep the engine temperature down.

There are two main types of cooling systems for marine engines: raw water cooling systems and closed-loop cooling systems. Both systems can be used for each engine in a dual-engine boat.

A raw water cooling system draws water from the surrounding sea or freshwater source through a seacock fitting. This water is then pumped through the engine's water jacket and out through the exhaust. The water absorbs heat from the engine, helping to keep it cool. This system is similar to a car's radiator, which uses air flow to cool the engine. However, as boats do not have access to airflow, they rely on the surrounding water instead.

A closed-loop cooling system, on the other hand, uses a combination of freshwater and coolant. This mixture is circulated through the engine and a heat exchanger, which helps to maintain the engine at a set temperature, usually between 170 and 180 degrees Fahrenheit. The raw water is pumped through the heat exchanger, where it absorbs heat from the freshwater mixture before being pumped out through the exhaust. This system is more effective in saltwater environments, as it prevents corrosive scale buildup inside the engine, which can occur when operating above 140 degrees Fahrenheit.

Both systems have their advantages, and it is important to regularly check and maintain the cooling system to ensure the engine's performance and longevity.

Alternating engines to balance hours

By using one engine at a time and alternating between them, boat owners can reduce engine wear and extend the life of their engines. This is because operating at a lower RPM reduces the hours of usage and the load on the engine, resulting in less wear and tear. Additionally, alternating engines helps balance the hours on each engine, ensuring they both have similar usage levels and reducing the likelihood of uneven wear.

Fuel economy is also improved when using a single engine at a lower RPM. For example, a boat owner with a Silverton 40 aft cabin boat reported achieving 1.5 MPG at 1800 RPM with one engine, compared to 0.4 MPG when using both engines at 2800 RPM. This improved fuel economy means lower operating costs and longer distances travelled between refuelling.

In addition to the economic and performance benefits, alternating engines can also improve manoeuvrability in tight spaces, such as when docking or trailering the boat. The ability to use opposing throttles with twin engines makes it easier to steer and navigate in confined areas.

However, it is important to note that alternating engines may not always result in better fuel efficiency or performance. In some cases, running both engines at a higher RPM can be more efficient, depending on the design and specifications of the boat. Additionally, the added weight of two engines and the hydrodynamic drag of two lower units can slow down the boat, affecting both acceleration and top-end speed.

Ultimately, the decision to alternate engines or use both simultaneously depends on various factors, including the boat's usage, the owner's priorities, and the specific characteristics of the boat and its engines. Boat owners should consider factors such as cost, performance, fuel economy, and maintenance when deciding whether to use one or both engines.

Safety courses for dual-engine boats

If you're looking to operate a dual-engine boat, several safety courses are available to ensure you're well-prepared and confident. These courses will cover essential topics such as boat handling, navigation, and engine operation, specifically for boats with two engines. Here's a detailed overview of what to expect:

Basic Safety Training and Certifications

Before working on any boat with multiple engines, it's crucial to obtain basic safety training and the necessary certifications. The STCW Basic Safety training and ENG1 medical certificate are mandatory for all crew members on a commercial yacht. The ENG1 medical certificate specifically assesses your medical fitness for working on a boat. Additionally, the MCA Engineering Officer training scheme is an internationally recognized pathway that can enhance your qualifications.

Approved Engine Course (AEC)

The Approved Engine Course (AEC) is an excellent entry-level qualification for those seeking to work with engines on commercial yachts or even skipper smaller yachts. While not compulsory, it is highly recommended for aspiring marine engineers. This four-day, 30-hour course covers both practical and theoretical aspects of diesel engine operation and associated systems. You'll learn about the principles of two-stroke and four-stroke engine operation, engine construction, electrical systems, fault-finding, and, importantly, safe working practices.

State-Specific Boating Safety Courses

Various organizations offer state-specific boating safety courses that are tailored to individual state regulations and requirements. For instance, the BoatUS Foundation provides free online boating safety courses developed specifically for your state. These courses are recognized by the U.S. Coast Guard and approved by the relevant state boating license agencies.

US Coast Guard Auxiliary Courses

The US Coast Guard Auxiliary also offers educational classes relevant to dual-engine boats. Their "Boating Skills and Seamanship" course covers legal requirements, rules of the road, navigation, charts, compasses, and boat handling. This course is typically offered over 13 weeks and is an excellent way to gain comprehensive knowledge about boating safety.

US Power Squadrons America's Boating Course

The US Power Squadrons provide basic boating knowledge through their America's Boating Course (ABC). This course is offered in both classroom and online settings and covers a range of topics, including required safety equipment, navigation rules, lights and sounds, government regulations, adverse conditions, and emergencies. Successful completion of this course meets the educational requirements for obtaining a California Boater Card (CBC).

California Boater Card Requirements

Speaking of the California Boater Card, it's important to note that as of January 1, 2024, all motorized vessel operators aged 60 and younger in California must complete a boating safety course and obtain this card before heading out on the water. The California Division of Boating and Waterways (DBW) offers an eCoursebook that meets this requirement and can be studied at your own pace. It covers federal navigation requirements, state and federal boating laws, boat handling, and more.

By enrolling in any of these comprehensive safety courses, you'll gain the knowledge and skills necessary to confidently operate a dual-engine boat while adhering to safety regulations.

Frequently asked questions