Yanmar 3GMF Marine Diesel Engine

The Yanmar 3GMF is a compact, fuel-efficient, and highly reliable inboard marine diesel engine delivering approximately 20–27 HP (depending on configuration and rating). Designed for auxiliary propulsion on sailboats and small cruising vessels, the 3GMF is part of Yanmar renowned GM series, known worldwide for durability, smooth operation, and long service life.

Engine Design & Construction

The 3GMF features a 3-cylinder, 4-stroke diesel configuration with direct mechanical fuel injection, providing responsive throttle control and consistent power output. Its robust cast-iron engine block and precision-engineered components are built to withstand continuous operation in demanding marine environments.

A freshwater cooling system with heat exchanger protects internal components from corrosion while maintaining stable operating temperatures. The compact engine footprint allows installation in tight engine rooms, making it ideal for repower projects.

Performance & Efficiency

Delivering dependable power for cruising, maneuvering, and docking, the Yanmar 3GMF offers strong low-RPM torque and smooth acceleration. The 3-cylinder layout minimizes vibration and noise, improving onboard comfort during long passages.

The efficient fuel injection system ensures excellent fuel economy, reducing operating costs while maintaining consistent performance.

Marine Integration

The Yanmar 3GMF is designed for shaft-drive inboard installations and is compatible with Yanmar marine gearboxes. Its predictable power delivery and precise throttle response make close-quarters handling easier in marinas and harbors.

Ease of Maintenance & Reliability

Yanmar engines are known for serviceability, and the 3GMF is no exception. Easily accessible service points simplify routine maintenance, while the engine’s mechanical design ensures long-term reliability. With Yanmar global service network, parts availability and technical support are widely accessible.

Ideal Applications

The Yanmar 3GMF Marine Diesel Engine is ideal for:

Sailboats and auxiliary propulsion systems
Small to mid-size cruising yachts
Coastal and offshore sailing
Repower and replacement projects

Key Advantages

Proven Yanmar marine diesel reliability
Compact and lightweight design
Fuel-efficient mechanical injection system
Freshwater cooling with heat exchanger
Smooth, low-vibration operation
Easy maintenance and long service life

Technical Specifications

General

Model: Yanmar 3GMF
Engine Type: 4-stroke, vertical, water-cooled marine diesel
Fuel System: Direct mechanical fuel injection
Aspiration: Naturally aspirated
Number of Cylinders: 3 inline

Displacement & Combustion

Displacement: Approx. 1.00 liter
Bore × Stroke: Approx. 75 mm × 76 mm
Combustion System: Direct injection diesel

Performance

Rated Power: Approx. 20–27 HP @ 3,400 RPM (depending on rating/version)
Maximum Speed: Approx. 3,400 RPM
Torque Characteristics: Strong low- and mid-range torque
Fuel Consumption: Economical, varies with load and propeller selection

Cooling & Lubrication

Cooling System: Freshwater cooling with heat exchanger
Lubrication System: Forced lubrication with trochoid oil pump
Engine Oil Capacity: Approx. 3.0 liters
Recommended Oil Type: Marine-grade diesel engine oil

Electrical System

Starting System: 12 V electric start
Alternator: 12 V marine alternator

Dimensions & Weight

Overall Dimensions (L × W × H): Approx. 670 × 500 × 560 mm
Dry Weight: Approx. 120–130 kg (engine only, excluding gearbox)

Drive & Installation

Rotation (Crankshaft): Counter-clockwise (viewed from flywheel end)
Drive Type: Inboard shaft drive
Compatible Gearbox: Yanmar marine transmission
Mounting: Flexible marine engine mounts

Service & Adjustment

Valve Clearance (Cold): Intake: 0.20 mm / Exhaust: 0.25 mm
Firing Order: 1 – 2 – 3
Maintenance Access: Easy access to filters, belts, and routine service components

Yanmar 3GMF

Yanmar 3GMF Marine Diesel Engine Sale