YANMAR 4JH45 45HP Common Rail Marine Diesel Engine – Compact Power and Clean Efficiency | JB Marine GmbH
JB Marine GmbH, Germany’s trusted Yanmar dealer, introduces the YANMAR 4JH45 45HP Marine Inboard Engine, a new generation of compact, fuel-efficient, and eco-friendly marine propulsion technology.
Designed for modern sailing yachts, catamarans, and light commercial vessels, the Yanmar 4JH45 delivers powerful performance and ultra-low emissions through its electronically controlled common rail (CR) fuel injection system.
Built for both reliability and sustainability, this 4-cylinder inboard diesel engine sets the standard for quiet operation, clean exhaust, and exceptional fuel economy.
Innovation Meets Marine Performance
The Yanmar 4JH45 45HP Marine Diesel Engine combines Yanmar’s advanced engineering with digital precision fuel control for optimized combustion, reduced vibration, and virtually smoke-free operation.
Thanks to its compact, lightweight design, the 4JH45 is ideal for new vessel builds and repowering projects, offering a perfect balance between space efficiency, durability, and performance.
It exceeds IMO Tier III and EPA Tier III emissions standards, ensuring cleaner oceans and compliance with the world’s strictest marine environmental regulations.
Engineered for Versatility and Reliability
Whether powering a monohull sailing yacht, a catamaran up to 50ft, or a light-duty commercial craft, the Yanmar 4JH45 provides consistent propulsion and smooth handling under all sea conditions.
With direct water-cooled heat exchanger technology and Bosch common rail fuel injection, this model ensures exceptional performance, reliability, and easy maintenance — perfect for long voyages or professional marine operations.
Key Features – Why Choose the Yanmar 4JH45 45HP
Compact Power, Big Performance
Delivers 45 horsepower from a 2.19L displacement — providing an ideal power-to-weight ratio for modern yachts and small commercial vessels.
Common Rail Technology
Electronically managed Bosch direct injection delivers precise fuel atomization, reducing fuel consumption, noise, and exhaust emissions.
Environmentally Responsible
Certified under IMO Tier III, EPA Tier III, and BSO II — ensuring cleaner, quieter, and more sustainable operation.
Lightweight, Space-Efficient Design
Compact footprint (770mm × 470mm × 670mm) and dry weight of 180kg, making installation simple in tight engine compartments.
Smooth and Quiet Operation
Vibration-dampened mounts and optimized combustion for silent running and superior comfort on board.
Factory-Installed Gearbox Included
Supplied with a KM35A or KM35P marine gearbox, ensuring seamless and efficient power transmission.
Easy Maintenance and Serviceability
Thoughtfully designed access points make routine service quick and straightforward.
Technical Specifications – Yanmar 4JH45 45HP Marine Inboard Engine
| Specification | Details |
|---|---|
| Rated Output | 45 HP / 3,000 RPM |
| Displacement | 2.19 Liters (134 cu in) |
| Number of Cylinders | 4 |
| Bore × Stroke | 88 mm × 90 mm |
| Fuel System | Common Rail, Bosch Direct Injection |
| Aspiration | Turbocharged |
| Cooling System | Freshwater with Heat Exchanger |
| Alternator | 12V – 125A |
| Dry Weight (without gear) | 180 kg |
| Dimensions (L × W × H) | 770 mm × 470 mm × 670 mm |
| Certifications | IMO Tier III, EPA Tier III, BSO II |
| Warranty | 5 Years Manufacturer’s Warranty |
Complete Package Includes
When you purchase the YANMAR 4JH45 45HP Diesel Marine Engine from JB Marine GmbH, your package includes:
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Yanmar 4JH45 Engine (brand new)
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Factory-installed gearbox (KM35A / KM35P)
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Turbocharger system
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Freshwater heat exchanger
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Exhaust mixing elbow (L-Type)
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Alternator (12V – 125A)
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Flexible engine mounts
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Fuel pre-filter with water separator
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Freshwater expansion tank
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B25 control panel
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Wiring harness (5m)
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Belt safety cover
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Comprehensive installation & operation manuals
Every engine is factory-tested, fully certified, and ready for professional installation.
Optional Accessories
Customize your Yanmar engine with genuine OEM accessories for enhanced performance:
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High-Riser Exhaust Mixing Elbow
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Secondary Alternator (12V – 125A / 24V – 60A)
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C35 Control Panel with advanced monitoring
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Extended Wiring Harness (3m / 5m / 10m)
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NMEA2000 Engine Monitoring System
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VC10 Vessel Control System
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SOLAS Certification Kit
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Hot Water Kit with Cocks
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Propeller Cone Nut Kit SD60
All optional accessories are Yanmar-certified for guaranteed compatibility and performance.
Environmental Leadership & Clean Propulsion
The Yanmar 4JH45 embodies Yanmar’s commitment to sustainable marine propulsion.
It utilizes common rail injection technology for precise fuel control, resulting in:
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Cleaner exhaust emissions
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Significantly lower NOx and particulate output
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Reduced fuel consumption
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Minimal vibration and noise levels
This makes it the ideal choice for eco-conscious boat owners and commercial operators seeking reliable, compliant power.
Applications
The Yanmar 4JH45 is designed for a variety of marine applications:
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Monohull Sailing Yachts
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Catamarans up to 50ft
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Light Commercial Boats
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Motorboats and Sloops
Its compact profile and light weight make it perfect for both new builds and repower projects.
Why Choose JB Marine GmbH – Authorized Yanmar Dealer in Germany
JB Marine GmbH is your trusted source for genuine Yanmar marine diesel engines in Europe, providing certified products, expert advice, and unparalleled customer support.
Why customers choose us:
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Official Yanmar Marine Dealer
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Factory-backed warranty and OEM parts
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Expert consultation for repower and new builds
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Professional installation assistance
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Fast, secure global shipping
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Comprehensive after-sales service
With JB Marine GmbH, you get authentic Yanmar quality, exceptional reliability, and full technical support — wherever your journey takes you.
Order Your YANMAR 4JH45 45HP Engine Today
Experience the perfect combination of compact power, fuel efficiency, and clean propulsion with the Yanmar 4JH45 45HP Diesel Marine Engine.
Contact JB Marine GmbH today for pricing, availability, and customization options.
Power your vessel with Yanmar’s latest common rail diesel technology — engineered for performance, built for the future.









