Coastal Marine Services, LLC

Information

2026 Mercury Marine® Mercury Diesel 550

Take your life on the water to new destinations with the Mercury Diesel 6.7L engine. This turbocharged workhouse redefines diesel performance for sport yachts and other large vessels, blending premium comforts and extended range with exceptional speed and acceleration

Features may include:

• The high-displacement turbocharged engine spools up massive torque, generating instantly responsive power to get big boats out of the hole and deliver a midrange punch when you need it.

• A thermostatically controlled closed-loop freshwater cooling system protects the engine in both fresh and saltwater.

• From vibration-dampening engine mounts to an air filter strategically positioned to also reduce turbo noise, the 6.7L engine is optimized for a smooth, quiet ride.

• The high-pressure common rail (HPCR) fuel injection system fine-tunes the air-to-fuel ratio to enhance acceleration, top speed and efficiency.

• The 6.7L engine is ready for all-season adventure, with a grid heater that makes cold weather starts easy

• Top-mounted fluid reservoirs, a self-draining oil filter and an easy-to-reach oil dipstick keep maintenance and service simple.

• With exceptional power-to-weight ratios, Mercury Diesel engines pack big-time propulsion in a lightweight package. The difference: quicker acceleration, faster planing and easier handling.

• Durability and reliability are in the details, like thermostatically controlled closed-cooling systems and advanced corrosion resistance. Our diesel engines are designed to go the distance.

• Mercury Diesel engines run clean and run easy, without the harshness or fumes from traditional diesels. They can also deliver up to 50% better fuel efficiency compared to gas engines of the same horsepower