Universal M25 XPBC Marine Diesel Engine

The Universal M25 XPBC is a compact, reliable, and fuel-efficient inboard marine diesel engine producing approximately 25 HP, specifically designed for sailboats and small cruising vessels. Known for its simplicity, durability, and smooth operation, the M25 XPBC has become a popular choice for auxiliary propulsion in a wide range of sailing applications.

Engine Design & Construction

The M25 XPBC features a 3-cylinder, 4-stroke diesel configuration with mechanical fuel injection, delivering dependable power and smooth torque across the operating range. Built on a robust industrial diesel platform adapted for marine use, it offers long service life and consistent performance in demanding marine environments.

A freshwater cooling system with heat exchanger ensures stable operating temperatures while protecting internal components from corrosion. Its compact design allows easy installation in tight engine compartments, and well-laid-out service points simplify routine maintenance.

Performance & Efficiency

Delivering approximately 25 HP, the Universal M25 XPBC provides reliable thrust for cruising, maneuvering, and docking. Its strong low- and mid-range torque characteristics make it ideal for displacement hulls and auxiliary sailboat propulsion.

The engine’s mechanical injection system ensures excellent fuel efficiency, keeping operating costs low while maintaining dependable performance over long operating hours.

Marine Integration

The Universal M25 XPBC is compatible with marine transmissions and conventional shaft-drive systems, offering flexibility for new installations or repower projects. Its balanced 3-cylinder layout helps reduce vibration and noise, improving onboard comfort during extended voyages.

Ease of Maintenance & Reliability

Designed for ease of service, the M25 XPBC provides convenient access to filters, belts, and routine service items. Its simple mechanical layout minimizes downtime and maintenance complexity. Backed by the long-standing Universal marine engine legacy, it benefits from good parts availability and service support.

Ideal Applications

The Universal M25 XPBC Marine Diesel Engine is ideal for:

Sailboats and auxiliary propulsion systems
Small cruising yachts
Coastal and inland waterways
Owners seeking a compact, economical, and reliable marine diesel engine

Key Advantages

Proven Universal marine diesel reliability
Compact and space-efficient design
Fuel-efficient 3-cylinder diesel engine
Freshwater cooling with heat exchanger
Smooth operation with reduced vibration and noise
Simple maintenance and long service life

Technical Specifications

General

Model: Universal M25 XPBC
Engine Type: 4-stroke, vertical, water-cooled marine diesel
Fuel System: Mechanical fuel injection
Aspiration: Naturally aspirated
Number of Cylinders: 3 inline

Displacement & Combustion

Displacement: Approx. 0.9 liters
Bore × Stroke: Approx. 72 mm × 73 mm
Combustion Chamber: Indirect injection diesel

Performance

Rated Power: Approx. 25 HP @ 3,000–3,200 RPM
Rated Speed: Up to 3,200 RPM
Torque Characteristics: Strong low- to mid-range torque for auxiliary propulsion
Fuel Consumption: Economical, dependent on load and propeller matching

Cooling & Lubrication

Cooling System: Freshwater cooling with heat exchanger
Lubrication System: Forced lubrication with gear-type oil pump
Engine Oil Capacity: Approx. 3.5 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. 820 × 480 × 570 mm
Dry Weight: Approx. 160–175 kg (engine only, excluding gearbox)

Drive & Installation

Rotation (Crankshaft): Counter-clockwise (viewed from flywheel end)
Drive Type: Inboard shaft drive
Compatible Gearbox: Universal 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 points