Buy Yanmar 4JH45 45HP marine diesel engine
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Yanmar

Yanmar 4JH45 45HP

$3,675.00

Yanmar 4JH45 — 45 HP liquid-cooled 4-cylinder marine diesel engine with direct injection for efficient and dependable propulsion.

Horsepower

45 HP

Fuel Type

diesel

Displacement

2.19 L / 131 cu. in

Rated Output

33.1 kW / 45 mhp

Rated Speed

3000 rpm

In Stock (3 available)
Free shipping on orders over $500
90-day warranty included

Description

Buy new Yanmar 4JH45 engines for sale or explore used Yanmar 4JH45 marine engines built for dependable marine performance. The Yanmar 4JH45 is a preferred choice for boat owners searching for reliable marine diesel engines, efficient propulsion systems, and long-lasting engine solutions. Designed for smooth operation and fuel savings, this engine supports marine upgrades and vessel performance across different applications. The Yanmar 4JH45 marine diesel engine delivers a combination of compact design, durability, and efficient power output. Engineered for dependable operation, this model performs consistently in recreational and professional marine environments while helping reduce operating costs over time. Built with a durable 4-cylinder platform, the Yanmar 4JH45 features advanced Bosch common-rail direct injection technology. This system improves fuel efficiency, supports cleaner combustion, lowers emissions, and reduces engine noise. The result is responsive acceleration and dependable marine performance in changing conditions. Ideal for sailboats, pleasure craft, and small yachts, the Yanmar 4JH45 provides stable propulsion and reliable output for long-distance cruising and daily marine use. Its compact construction supports efficient installation while maintaining strong and consistent operation. Boat owners looking to buy used Yanmar 4JH45 engines or searching for new marine engines for sale continue to select this model for vessel replacement projects, marine upgrades, and dependable diesel performance. Supported by trusted engineering and global service availability, the Yanmar 4JH45 remains a proven choice for long-term marine operation. Key Features: • Yanmar 4JH45 marine diesel engine • Durable 4-cylinder engine configuration • Bosch common-rail direct injection technology • Improved fuel efficiency • Lower emissions output • Reduced engine noise and smoother operation • Compact and durable marine construction • Ideal for sailboats and small yachts • Dependable marine propulsion performance • Built for long-term reliability

Specifications

SKUY712146
BrandYanmar
CategoryInboard Engines
ConditionNew
Horsepower45 HP
Fuel Typediesel
Displacement2.19 L / 131 cu. in
No. of Cylinders4 cylinders
Rated Output33.1 kW / 45 mhp
Rated Speed3000 rpm
Cylinder Bore x Stroke88 mm x 90 mm / 3.46 in x 3.54 in
Combustion SystemDirect Injection, Bosch Common Rail System
AspirationNatural
Alternator12V - 125A
Dry Weight220 kg / 485 lbs
Dimensions870 mm x 589 mm x 627 mm
ControlsMechanical
CertificationsRCD 2 EPA Tier 3 EPA Tier 3C BSO II EMC SOLAS

Frequently Asked Questions

What is the Yanmar 4JH45 engine?

The Yanmar 4JH45 is a 4-cylinder, 4-stroke, vertical water-cooled diesel marine engine producing about 45 metric horsepower (mhp) at 3000 rpm. It belongs to Yanmar’s JH-CR (Common Rail) series, known for modern diesel technology and reliable operation in marine applications.

What are the main technical specifications?

Rated Output: ~33.1 kW / 45 mhp at 3000 rpm Displacement: 2.19 L (131 cu in) Cylinders: 4 inline Combustion: Direct injection with Bosch Common Rail system Aspiration: Naturally aspirated Alternator: 12 V – 125 A Dry Weight (no gear): ~220 kg / 485 lbs Dimensions: 870 × 589 × 627 m Controls: Mechanical (optional VC10 electronic system)

What fuel system does this engine use?

The 4JH45 uses a Bosch Common Rail direct injection fuel system, providing smoother combustion, improved fuel efficiency, reduced emissions, and quieter operation compared to older mechanical pumps.

What types of boats is the 4JH45 suited for?

It’s commonly used in sailboats, catamarans, small yachts, and custom recreational vessels where reliable medium-power propulsion is needed. Its size and power make it ideal for boats around ~8–12 m (26–40 ft)

What are standard components included with the engine?

Exhaust mixing elbow (L-type) Freshwater expansion tank Fuel pre-filter with water separator Flexible engine mounts B25 engine panel Mechanical throttle sensor Belt safety cover

Are there optional accessories available?

Yes — you can add accessories such as: Secondary alternator (12 V or 24 V). Extended harnesses. TFX sidemount control head. VC10 vessel control system. NMEA2000 engine monitoring. Hot water kits and more.

What kind of cooling system does it use?

The engine uses a freshwater cooling system with a heat exchanger and a seawater pump with rubber impeller. This protects the engine from corrosion and helps maintain stable operating temperatures.

What transmission options are compatible?

Common marine gear options include KM35P, KM4A2, ZF25A, ZF30M, and SD60 saildrive, depending on boat configuration and installation preferences.

What maintenance should be done regularly?

Engine oil & filter changes at regular hourly intervals Fuel filter and water separator servicing Coolant checks and seawater impeller inspection Belt and hose condition checks

How fuel efficient is the 4JH45?

Actual consumption varies with boat load and cruising speed, but engines with common rail technology are generally more fuel-efficient and produce better torque at lower rpms than older designs. Precise consumption figures depend on settings and conditions.