BMW Z4 Series E85 2.5i 2.5si N52 Complete Engine N52B25A with 79k miles WARRANTY

Warranty and technical condition of the part

The engine is sold with a 90-day warranty.

The warranty covers the engine itself; engine accessories are covered by a 30-day warranty.

The power unit was tested before removal and is in full working order.

Listing details

The offer applies to a complete engine.

The engine comes from a right-hand drive (RHD) vehicle. The wiring harness is not compatible with left-hand drive (LHD) vehicles and requires replacement or modification.

BMW Z4 Series E85 2.5i 2.5si N52 Complete Engine is a complete powertrain from the BMW six-cylinder petrol engine family, designed for Z4 E85 models in 2.5i and 2.5si versions. This is a solution for users looking for a proven, used engine with a modern design, which allows for restoring full powertrain efficiency without the costly regeneration of an old unit. By maintaining factory specifications, the engine ensures the refined operation and linear power delivery characteristic of BMW.

Specifications and technical data

• SKU: p0421071-1
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 0421071
• Substitutable numbers: 11000421071, 0421071, 11000421072, 0421072
• Fuel type: Petrol
• Number of cylinders: 6
• Category: Engines
• Engine code: N52B25A
• Mileage: 59 000

Technical characteristics of the N52B25A unit

The offered engine belongs to the N52 family, which are modern, inline six-cylinder BMW petrol units. This configuration ensures excellent balance, low vibration, and smooth power delivery across the entire rev range. The design of the N52B25A was engineered for dynamic driving, typical of Z4 models, while maintaining reasonable fuel consumption and high operational refinement.

The engine is designed for petrol fuel, which facilitates the selection of accessories, fuel injection, and ignition systems consistent with factory BMW solutions. The use of six cylinders in an inline layout promotes even mechanical load, which is significant for long-term operation and when designing modifications, such as engine control unit software changes.

Purpose and compatibility with BMW Z4 E85

The BMW Z4 Series E85 2.5i 2.5si N52 Complete Engine has been configured for installation in the BMW Z4 E85 in 2.5i and 2.5si versions, which significantly simplifies the engine replacement process. Maintaining the correct engine code allows for proper cooperation with the vehicle's factory electronics, wiring harness, and cooling and lubrication systems, minimizing the risk of compatibility issues.

The unit will work well both as a replacement in the event of a failure of the current engine and for modernization projects where the priority is to maintain the original handling characteristics of the BMW Z4 E85. This allows for the restoration of the car's factory performance without the need to interfere with the body structure or the powertrain.

Condition, mileage, and benefits of choosing a used engine

The engine comes from the Engines category and is offered as a used item, which allows for a significant reduction in repair costs compared to purchasing a new unit or a full overhaul. The declared mileage allows for an assessment of the wear level and the planning of any necessary service activities after installation, such as changing the oil, filters, or spark plugs.

Choosing a used, complete engine is particularly beneficial in situations where the existing unit has suffered serious mechanical or thermal damage. Instead of investing in a costly rebuild, a complete powertrain with a known code can be used, which shortens vehicle downtime and simplifies the workshop process.

Practical installation tips and selection by engine code

Before installation, it is recommended to verify the compatibility of the engine code with the vehicle documentation and diagnostic systems to ensure full cooperation with the existing controller and accessories. In workshop practice, it is also important to check the condition of consumables and seals so that the engine can operate stably and without leaks after installation.

To facilitate the identification and selection of spare parts, the unit has an assigned engine code, which allows for precise searching for compatible components in BMW catalogs and independent parts databases. This allows for controlled planning of further service work and potential upgrades.

Expanding the BMW powertrain – Engines category

If you are planning a comprehensive repair or upgrade of the engine area in your BMW and need other elements from the same group, such as blocks, cylinder heads, or complete powertrains, check the available parts in the BMW Engines category.

More about buying used engines – expert guide

When choosing a used engine, it is worth relying on reliable technical data, selection procedures based on identification numbers, and real examples of repair costs. A detailed discussion of the advantages and limitations of such solutions, along with practical tips for workshops and users, can be found in the article Why it is worth buying used gearboxes and engines – facts instead of myths, which helps in making informed purchasing decisions.