Oil Separator BMW E87 E90 E91 N46 Connecting Line Pipe Hose 7503523

Oil Separator BMW E87 E90 E91 N46 Connecting Line Pipe Hose is a component from the Lines, hoses and pipes group, responsible for the proper discharge of oil vapors from the crankcase ventilation system in BMW engines. A properly selected oil separator hose stabilizes engine operation, reduces intake contamination, and supports uniform engine lubrication.

Specifications and technical data

• SKU: 7503523
• Mark: BMW (Genuine OE)
• Condition: Used
• OEM Part Number: 7503523
• Substitutable numbers: 11157503523, 7503523
• Category: Hoses, Lines & Pipes

Function and role of the crankcase ventilation hose in the BMW N46 engine

The oil separator hose in BMW N46 family engines is responsible for the controlled discharge of gases from the crankcase and their reintroduction into the intake system. A properly functioning crankcase ventilation hose:

• stabilizes pressure in the crankcase,
• limits oil from entering the intake,
• supports cleaner operation of the intake system and valves,
• reduces the risk of leaks and "false" air intake.

For BMW N46 units, using the correct oil separator hose has a direct impact on engine performance, smooth idle speed, and proper interaction with the engine management system.

Compatibility with BMW E87, E90, E91 models

The offered crankcase ventilation hose is designed for use in popular BMW 1 and 3 series models of the E87, E90, and E91 generations with the N46 engine. This makes it a practical solution for both private users and workshops specializing in BMW maintenance.

Selecting an oil separator hose compatible with the specific engine version and body style helps avoid fitment issues, leaks, and incorrect hose routing in the engine bay.

Benefits of using an original BMW oil separator hose

The component from the Lines, hoses and pipes group originating from BMW ensures the correct geometry, diameter, and flexibility of the hose, which translates into:

• a secure, airtight connection with the crankcase ventilation system ports,
• resistance to temperature and contact with oil vapors,
• stable routing of the hose in the engine bay without tension.

A hose constructed in this way helps reduce typical symptoms of crankcase ventilation system wear, such as increased oil consumption, unstable idle, or oiling of intake components.

Product condition and service application

The offered BMW oil separator hose is a used component, making it an attractive cost-effective solution while maintaining the manufacturer's original specifications. It can be used both for standard replacement of a worn hose and for broader service work related to the crankcase ventilation system in the N46 engine.

Replacing the crankcase ventilation hose is recommended if cracks, material hardening, leaks, or visible oiling at the connections are detected. Using the appropriate hose helps restore correct engine operating parameters and reduces the risk of secondary failures.

Support with selection and additional information

When selecting an oil separator hose for a specific BMW version, it is worth using the manufacturer's markings and vehicle data to ensure full compatibility with the crankcase ventilation system. If in doubt, it is helpful to compare the hose routing, shape, and connector type with the component installed in the vehicle.

If you are planning a comprehensive repair or upgrade of the engine area in your BMW and need other components from the same group, such as vacuum lines, cooling system hoses, or breather pipes, check the available parts in the BMW lines, hoses and pipes category.

For users who want to consciously choose components from the secondary market and optimize service costs, a guide describing the principles of safe purchase of used components may be useful – you can find it in the article Safe purchase of used car parts online – a step-by-step guide.