Sleeves with code EN170H13 are precision-engineered components used in the MAN L21/31 engine to provide wear protection, alignment, or sealing between moving and stationary parts. Produced from high-quality alloy steel, these sleeves offer excellent resistance to abrasion, thermal stress, and mechanical loading. By maintaining correct clearances and protecting base components from wear, they play a vital role in extending component life, ensuring smooth operation, and reducing maintenance intervals in demanding marine and industrial environments.

The pipe with code 2101793-2.0 is an essential fluid-transfer component within the MAN L21/31 engine, used for conveying lubricating oil, cooling water, fuel, or air between critical engine systems. Designed to withstand high pressure, temperature fluctuations, and continuous vibration, this pipe ensures reliable and uninterrupted flow under demanding operating conditions. Its precise routing and robust material selection help maintain system efficiency, reduce the risk of leaks, and support long-term engine reliability in marine and power-generation applications.

The bearing stand H 45338 is a structural support component designed to house and stabilize bearing assemblies within the Sulzer ASL25 engine. Engineered to absorb high radial and axial loads while maintaining precise alignment, this bearing stand ensures smooth rotation of associated shafts and reliable load distribution under continuous operation. Manufactured from high-strength material with strict dimensional tolerances, H 45338 contributes significantly to vibration reduction, bearing longevity, and the overall mechanical integrity and durability of the engine.

The hydraulic tie rod with code 0743814-5.3 is a precision tensioning component used in the MAN L21/31 engine to secure the cylinder head and crankcase assembly with uniform clamping force. By applying controlled hydraulic pressure during tightening, the tie rod ensures even load distribution, compensates for thermal expansion, and minimizes distortion under high combustion pressures. This system enhances sealing reliability, reduces mechanical stress, and significantly improves engine durability, particularly during long operating cycles and frequent load variations.

The cylinder crankcase with code 11.01200-3593-1.L forms the core structural foundation of the MAN L21/31 engine, housing the crankshaft, main bearings, and lower sections of the cylinder assembly. Designed to withstand high combustion forces, torsional loads, and continuous thermal stress, the crankcase ensures precise alignment of all rotating components. Its rigid construction is essential for minimizing vibration, maintaining lubrication integrity, and guaranteeing long-term reliability in demanding marine propulsion and power generation applications.

The connecting rod with cover H 33001 is a critical power-transmission assembly in the Sulzer ASL25 engine, responsible for converting the linear motion of the piston into rotational motion of the crankshaft. Engineered to withstand extreme tensile and compressive forces generated during combustion, this component ensures precise bearing alignment and efficient load transfer. Its robust construction, precision machining, and balanced design minimize vibration and bearing wear, making it essential for reliable engine performance, mechanical integrity, and long service life under continuous heavy-duty operation.

Compact Power. Made in Croatia.

High-Performance. Precision-Built. EU-Tested.

From Karlovac — Home of Croatian Heavy Industry Since 1949.

The ADR3AP is a state-of-the-art small diesel engine designed and manufactured by Adriadiesel d.d., a company with over 70 years of experience in powering critical infrastructure across the globe.

Despite its compact form factor, the ADR3AP delivers exceptional efficiency, robust power output, and service-friendly architecture — making it ideal for use in marine systems, industrial generators, OEM solutions, and backup power units.

Whether you need performance in demanding coastal conditions, reliability for industrial uptime, or flexibility for hybrid energy systems — the ADR3AP delivers. Fully developed, assembled, and tested in Karlovac, Croatia, this engine embodies the very best of European mechanical engineering and quality assurance.

 

Over 70 Years of Diesel Power Engineering

Trusted Heritage. Proven Performance.

Adriadiesel d.d., headquartered in Karlovac, was originally part of the prestigious Jugoturbina industrial complex, established in 1949. Since then, Adriadiesel has evolved into a specialist diesel engine manufacturer known for its custom-built engines, reliability in harsh environments, and export-quality standards.

With a global reference list spanning Europe, the Middle East, Africa, and Central Asia, Adriadiesel supports sectors ranging from naval propulsion and off-grid energy to defense and hydropower backup.

Today, we combine that tradition with new infrastructure — including a newly built, EU-financed test station capable of testing small diesel engines on dynamometers up to 895 kW, or 3,344 kW using a water brake.

We are one of the few companies in the region offering full in-house testing, certification, and customization — from 10 kW to multi-megawatt diesel systems.

 

ADR3AP Diesel Engine — Technical Highlights

Feature	Value
Engine Type	ADR3AP
Engine Family	C
Displacement	2.5 L
Prime Power Output	60 kW
Standby Power Output	65 kW
Speed	1500 rpm
Weight	250 kg
CE Certified	Yes
Country of Origin	Croatia (EU)
Manufacture Date	July 2025

 

Customization Available on request

Every ADR3AP engine undergoes thorough inspection, performance testing, and documentation — ensuring it meets EU market standards, marine or stationary compliance, and client-specific needs.

 

Visual Gallery & Technical Commentary

Engine Side View with Radiator

A complete side view of the ADR3AP diesel engine mounted on a custom transport platform.

Notice the fully integrated radiator, rigid pipe routing, and robust steel frame — optimized for both vibration isolation and transport stability.

 

Radiator Front View

The ADR3AP’s radiator is designed for continuous operation, with anti-corrosive coating, safety grid, and optimized airflow for 1500 rpm cooling cycles — especially important in enclosed generator or marine environments.

 

Top Logo View

The Adriadiesel-branded valve cover represents over seven decades of diesel engine heritage. This signature branding also assures traceability, production origin, and quality certification.

 

Flywheel Housing View

Rear view showing the flywheel interface — designed for compatibility with multiple generator coupling configurations, SAE housings, or direct-drive systems.

 

Fuel System & Filters Close-up

A technical close-up of the fuel injection rail, dual-stage filtration system, and sensor wiring. This design ensures stable fuel pressure and clean combustion even in remote or harsh environments.

 

Top-Down Full Engine Layout

Full view reveals a service-accessible layout, clean separation of air, fuel, and exhaust systems, and tight packaging — all contributing to ease of integration into OEM or genset enclosures.

 

Alternate Side View

A different angle showcasing the air intake filter, alternator mounting, and coolant routing — proof of the careful mechanical layout and modern component integration.

 

Wiring & Filter Close-Up

Close-up of the sensor and wiring harness, showing attention to serviceability and diagnostics. Well-labeled, corrosion-protected terminals allow easy integration with control panels and monitoring units.

 

Adriadiesel LinkedIn Profile

 

Follow us on LinkedIn! Get real-time updates on engine deliveries, new products, certifications, and international partnerships from Adriadiesel d.d., Croatia.

Applications & Use Cases

• Marine auxiliary engines
• Gensets for commercial vessels and yachts
• Mobile generator platforms
• Backup diesel power for industry or hospitals
• Energy systems in remote or island locations
• Defence, border, and civil protection infrastructure

 

Available Services

• Custom genset enclosure design
• Emission optimization packages
• Factory acceptance testing (FAT)
• Remote commissioning and on-site startup
• Spare parts and technical manuals
• CE conformity packages & EU declarations

 

Let us Build Your Power Solution Together

 

Visit us at: www.adriadiesel.hr
Follow us on LinkedIn: Adriadiesel d.d.
Email: This email address is being protected from spambots. You need JavaScript enabled to view it.

Built in Karlovac. Shipped worldwide.

The intermediate piece with code 11.41199-0008.0 serves as a precision connecting element within the MAN L21/31 engine assembly, providing accurate alignment and secure mechanical integration between adjoining components. Designed to withstand vibration, thermal expansion, and dynamic loading, this component ensures correct geometry of the engine system and smooth transfer of forces between connected structures. Its dimensional accuracy and material integrity are essential for long-term operational stability and low-maintenance performance in demanding marine and industrial environments.

The piston H 34001 is a core combustion component of the Sulzer ASL25 engine, designed to withstand extreme thermal loads, high combustion pressures, and continuous mechanical stress. Manufactured from high-strength alloy with optimized geometry and surface treatment, it ensures efficient force transfer, reduced friction, and controlled oil consumption. Its precision engineering supports stable engine performance, low emissions, and long-term reliability, making H 34001 essential for demanding marine and power-generation applications.

The adjustment screw H 27217 is a precision control component used in the valve train system of the Sulzer ASL25 engine, enabling accurate setting of valve clearance and timing parameters. Designed to maintain stable positioning under vibration, thermal expansion, and continuous mechanical load, this screw ensures consistent engine performance and protects critical valve components from premature wear. Manufactured from high-strength material with precise threading, H 27217 provides reliable adjustment, long-term dimensional stability, and contributes directly to efficient combustion and smooth engine operation.

The gasket, code 06.56936-2355.0, serves as a vital sealing interface in the MAN L21/31 engine, preventing leakage of oil, coolant, and combustion gases between joined surfaces. Engineered from heat- and pressure-resistant materials, this gasket ensures tight, stable sealing under continuous high-temperature operation and dynamic load conditions. By maintaining system integrity and preventing contamination between engine circuits, it plays a direct role in operational efficiency, environmental compliance, and reduced maintenance requirements.

The sealing ring H 21423 is a critical sealing component used in various fluid and pressure interfaces of the Sulzer ASL25 engine. Designed to provide a tight, leak-free barrier under varying pressure, temperature, and vibration conditions, this sealing ring protects internal engine components from contamination and prevents loss of working fluids. Manufactured from high-quality, application-optimized material, H 21423 ensures long service life, stable sealing performance, and contributes directly to the operational safety and efficiency of the engine.

The conical clamping ring H 27078 is a precision-engineered securing component used in the Sulzer ASL25 engine to provide strong, vibration-resistant axial locking of critical assemblies. Its conical geometry generates uniform radial pressure during tightening, ensuring stable positioning and reliable retention of associated components under high mechanical loads and thermal cycling. Manufactured from high-strength material with accurate surface finish, this clamping ring minimizes micro-movement, reduces wear on mating parts, and contributes significantly to the long-term mechanical stability and operational reliability of the engine.

The axial bearing disc, code 11.10121-0122.0, plays a critical role in managing axial forces acting on the crankshaft in the MAN L21/31 engine. By absorbing and distributing thrust loads generated during engine operation, it prevents excessive axial movement of the shaft and protects adjacent bearing surfaces from premature wear. Its robust construction and precise tolerances are essential for maintaining stable crankshaft positioning, reducing vibration, and ensuring reliable engine performance under variable load conditions.

Kompletni ventil goriva H 27200 precizno je izrađena ubrizgavačka komponenta zadužena za doziranje i raspršivanje goriva u komoru za izgaranje motora Sulzer ASL25. Projektiran za rad pri visokim tlakovima i preciznu kontrolu protoka, ovaj ventil osigurava optimalnu raspodjelu goriva, učinkovito izgaranje i smanjene emisije. Izrađen od visokokvalitetnih materijala uz uske tolerancije, H 27200 zadržava stabilne performanse ubrizgavanja pri ekstremnim toplinskim i mehaničkim opterećenjima, čineći ga ključnim za stabilnu snagu motora, dobru iskoristivost goriva i dug vijek trajanja u zahtjevnim brodskim i industrijskim uvjetima.

The complete fuel valve assembly H 27200 is a precision-engineered injection component responsible for delivering and atomizing fuel into the combustion chamber of the Sulzer ASL25 engine. Designed for high-pressure operation and precise flow control, this valve ensures optimal fuel distribution, efficient combustion, and reduced emissions. Manufactured with high-grade materials and tight tolerances, H 27200 maintains consistent injection performance under extreme thermal and mechanical loads, making it essential for stable power output, fuel efficiency, and long service life in demanding marine and industrial environments.

The guide bearing cap, code 11.01254-0169.A, provides axial guidance and positional stability for the crankshaft in the MAN L21/31 engine. By maintaining accurate alignment under fluctuating loads and thermal expansion, it helps control crankshaft movement and reduces mechanical wear. Its precision construction supports smooth engine operation, protects critical rotating components, and contributes significantly to the overall reliability and service life of the engine under demanding operating conditions.

The cylinder crankcase, code 11.01203-1642-1.T, is the core structural housing of the MAN L21/31 engine, supporting the crankshaft, main bearings, and cylinder assemblies while absorbing the immense mechanical forces generated during combustion. Engineered for high rigidity and vibration damping, this heavy-duty component ensures precise alignment of all rotating parts and provides the foundation for stable, low-noise engine operation. Its robust design is essential for long service life and reliable performance in continuous marine propulsion and industrial power generation environments.

The spring H 27705 is a critical control element in the valve train of the Sulzer ASL25 engine, responsible for maintaining precise valve timing by ensuring rapid and consistent valve closure during each engine cycle. Engineered for high fatigue resistance and dimensional stability, this spring performs reliably under repeated compression, elevated temperatures, and continuous dynamic loading. Its carefully calibrated stiffness guarantees optimal contact between camshaft, valve, and rocker mechanism, contributing directly to efficient combustion, reduced mechanical wear, and smooth long-term engine operation.

The pipe clamp, code 06.66012-1101.0, is an important support component in the MAN L21/31 engine, used to securely fasten pipes and hoses to the engine structure. It prevents unwanted movement, vibration, and mechanical stress on fluid lines, reducing the risk of fatigue or leakage. Designed for durability and precise fit, the pipe clamp supports safe routing of oil, fuel, and cooling lines, contributing to orderly installation, easier maintenance, and dependable engine operation in harsh marine and industrial environments.