Engine Specifications:
The D2-50 engine has a crankshaft power of 37.5 kW (51 hp) and a propeller shaft power of 36 kW (49 hp), operating at an engine speed of 2700–3000 rpm. It features a displacement of 2.2 liters (134.2 in3) with four cylinders, a bore/stroke of 84/100 mm (3.31/3.94 in.), and a compression ratio of 23.3:1. The dry weight varies depending on the configuration: 249/243 kg (549/536 lb) with reverse gear HS25A/MS25, and 253 kg (558 lb) with saildrive 130S/SR. The engine complies with BSO, EU RCD Stage II, and US EPA Tier 3 emissions standards and is rated R5 for pleasure craft applications.

Technical Description:
The engine block and head are made from high-grade cast iron, featuring a rigid tunnel block design. The crankshaft is chrome molybdenum forged, balanced with integral counterweights. Pistons are made from high silicon aluminum with two cast iron, chromium-faced compression rings and a single oil ring. The engine includes replaceable, hardened valve seats and an elastic coupling on the flywheel.

Systems and Components:
- Engine Mounting: Features tuned front and rear cushion-type rubber mounts that are adjustable.
- Lubrication System: Includes a spin-on full-flow oil filter, separate oil scavenger pipe, and closed circuit crankcase ventilation.
- Fuel System: Comprises a flange-mounted, cam-driven in-line injection pump, feed pump with hand primer, spin-on type fine fuel filter, and an auxiliary stop button.
- Exhaust System: Freshwater cooled exhaust manifold and seawater cooled exhaust elbow.
- Cooling System: Freshwater cooling system with a thermostat, tubular heat exchanger with integral expansion tank, and accessible sea water pump and impeller.
- Electrical System: 12V corrosion-protected system with a 115A marine alternator, optional 24V alternator, charging regulator, glow plugs, electric starter motor, and electrical stop.

Options and Accessories:
Options include separate instruments for fuel level, temperature, voltage, an LCD display with multisensor, and an NMEA interface. Transmission choices include HS25A Hydraulic, MS25A Mechanical, and MS25L Mechanical, with various ratios. Accessories available include engine controls, extra alternator kits, battery systems, hot water systems, cooling water components, exhaust systems, fuel systems, and more.

Additional Information:
Not all models and accessories are available in all countries, and specifications are subject to change without notice. For more information, contact a Volvo Penta dealer or visit their website.