Yanmar 3YM30 – Marine Diesel Engine 29 HP

Deliver 29 horsepower at 3200 RPM directly to your sailboat propeller shaft with the Yanmar 3YM30. This 3-cylinder naturally aspirated diesel motor relies on a 1.115-liter displacement block, providing reliable auxiliary propulsion for cruising sailboats and small workboats. Indirect fuel injection keeps mechanical noise down inside the cabin, while a mechanical cone clutch transmission gives you positive gear control when backing into a slip.

Keeping salt corrosion away from internal cylinder walls is handled by a closed freshwater cooling system with an integrated heat exchanger. The engine mounts on a standard SAE 5 flywheel housing, spinning a 12V 60-amp alternator to keep your house battery banks topped off. With a dry weight of 127 kg (280 lbs), it delivers solid mechanical power without dragging down the stern of your vessel.

Engine Performance and Engineering

Smooth power delivery and low noise make this Yanmar inboard engine a favorite among sailboat owners. Forced lubrication with a trochoid pump circulates oil continuously, protecting crank bearings under heavy loads. The wet mixing elbow dampens exhaust pulses before water leaves through the transom.

Why Choose the Yanmar 3YM30 Inboard Marine Engine

Sailboat owners pick the 3YM30 marine engine for its lightweight 1.115-liter block and dependable 29 horsepower output. Its closed heat exchanger cooling protects internal waterways from salt corrosion, while the mechanical cone clutch provides crisp shifting. Compatibility with both shaft transmissions and saildrives makes this model an easy repower choice.

Warranty and Support

Yanmar backs this engine with a 2-Year Limited Recreational Warranty covering major engine block assembly components against defects. provides product-information support before purchase and assistance with order-related questions. Prior to freight shipment, staff verify the crated engine package against the confirmed order details. Review warranty eligibility and current coverage details on before placing your order.

Before Ordering the Yanmar 3YM30 Inboard Marine Engine

Measure your engine room compartment height and stringer width to ensure the SAE 5 housing and oil dipstick clear all bulkheads. Confirm your propeller shaft diameter, coupling bolt pattern, or saildrive hull cutout dimensions match this engine configuration before placing your order.