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Monday, 19 January 2026 09:26

ADR3AP DIESEL ENGINE

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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

ADR3AP 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

ADR3AP 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

ADR3AP engine 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

ADR3AP engine flywheel 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

ADR3AP engine fuel system detail

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

ADR3AP engine top down complete view

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

ADR3AP engine left 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

ADR3AP engine filter and wiring closeup

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

ADRIADIESEL LinkedIn

 

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 thermostat housing with code 11.41100-0626.0 forms the protective and functional enclosure for the cooling water thermostat in the MAN L21/31 engine. This robust housing ensures proper coolant routing, pressure containment, and leak-free operation within the engine’s cooling circuit. Engineered for high thermal resistance and mechanical strength, the thermostat housing plays a vital role in maintaining precise temperature control, safeguarding internal components, and ensuring reliable engine operation under continuous load conditions.

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 cooling water thermostat with code 11.06011-0073.0 is a critical temperature-regulating component in the MAN L21/31 engine, responsible for maintaining the engine within its optimal operating temperature range. By automatically controlling coolant flow based on thermal conditions, the thermostat ensures rapid warm-up, stable combustion performance, and effective protection against overheating. Its precise response characteristics directly contribute to improved fuel efficiency, reduced mechanical wear, and extended service life — especially under continuous heavy-duty marine and power-generation operation.

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