Yanmar 4JH45 – Marine Diesel Engine 45 HP

Description

Helms and engine rooms requiring 45 hp from a 2.19L inline four-cylinder platform can use the Yanmar 4JH45 with common rail injection and naturally aspirated induction. The engine reaches its stated output at 3,000 rpm and uses EN 590 diesel. Mechanical or saildrive transmission options, electronic-control compatibility, and KM35A2, KM35P, or SD60 drive arrangements define the specified propulsion integration choices.

The 485-pound dry engine uses an SAE 4 flywheel housing, a 12V 125-amp alternator, and enclosed forced lubrication with 5.0L oil capacity. Heat-exchanger cooling holds 7.2L coolant, while the wet mixing elbow forms part of the documented exhaust system. Listed emissions ratings include EPA Tier 3, RCD II, and BSO II.

Key Specifications of the Yanmar 4JH45 Marine Diesel Engine

• The 2.19L inline four-cylinder engine produces 45 hp at 3,000 rpm through a naturally aspirated common rail diesel configuration.
• Common rail injection and EN 590 fuel requirements define the documented fuel-system specification for the stated 17.0:1 compression ratio.
• Mechanical or saildrive transmission choices require drivetrain planning around the SAE 4 flywheel housing and selected vessel layout.
• KM35A2, KM35P, and SD60 drive options define the listed propulsion interfaces for compatible repower or new-build installations.
• A 12V 125-amp alternator provides the stated charging output for vessels using this engine electrical-system configuration.
• Heat-exchanger cooling and a wet mixing elbow establish the documented cooling-water and exhaust-routing arrangement.
• Enclosed forced lubrication uses 5.0L oil capacity, while the cooling system holds the stated 7.2L coolant volume.

Engine Configuration and Service Access

This Yanmar marine diesel engine uses an inline four-cylinder, four-stroke configuration with 88 by 90 mm bore and stroke dimensions. Its stated 1-3-4-2 firing order, 220 kg dry weight, and electronic-control compatibility are relevant when planning engine-bed loading, controls, and access around the installed unit.

Common rail fuel components, cooling plumbing, lubrication-service points, alternator connections, and wet-exhaust routing should remain accessible after installation. These systems should be planned together with the selected mechanical or saildrive transmission arrangement.

Why Choose the Yanmar 4JH45 Marine Diesel Engine

The 4JH45 marine diesel engine combines 45 hp at 3,000 rpm with common rail injection in a naturally aspirated 2.19L four-cylinder layout. Buyers can compare its 12V 125-amp alternator, electronic-control compatibility, mechanical or saildrive transmission choices, and listed KM35A2, KM35P, or SD60 drive options. Its EPA Tier 3, RCD II, and BSO II ratings provide additional specification context.

Installation and Compatibility Considerations

Confirm the vessel supports the 485-pound dry weight, engine-bed arrangement, SAE 4 flywheel housing, chosen mechanical or saildrive transmission, and KM35A2, KM35P, or SD60 drive interface. Plan fuel supply, cooling-water intake, wet-exhaust routing, control wiring, 12V charging connections, ventilation, and propeller or saildrive alignment before installation.

Use EN 590 diesel and provide access for common rail fuel-system inspection, 5.0L oil servicing, and 7.2L coolant maintenance. Verify electronic-control compatibility with the planned helm controls and follow the applicable Yanmar installation and commissioning documentation.

Warranty and Support

This model is eligible for Yanmar’s 3-Year Extended Limited Warranty program for first retail purchasers, subject to private and recreational use requirements. For product details and order support, Mulmarine.com offers assistance before your purchase is placed. Current coverage information and warranty eligibility are available for review on Mulmarine.com before ordering.

Before Ordering the Yanmar 4JH45 Marine Diesel Engine

Before ordering, verify engine-bed dimensions, mount locations, transmission choice, SAE 4 flywheel-housing compatibility, and the required KM35A2, KM35P, or SD60 drive arrangement. Confirm your vessel has EN 590 diesel fuel supply, suitable cooling-water and wet-exhaust systems, compatible electronic controls, 12V wiring, ventilation, and a professional plan for final propulsion alignment.