CORTECO 12015381 FPM BAVISLDRWX7 38x50x7 - Engine Shaft Oil Seal for BMW and Piaggio

CORTECO 12015381 is an FPM/FKM radial shaft oil seal with dimensions 38x50x7 mm, designed for specific engine shaft applications in BMW and Piaggio vehicles. The BAVISLDRWX7 construction is intended for demanding automotive sealing positions where the sealing lip operates against a rotating shaft in contact with engine oil. The FPM fluoroelastomer provides enhanced resistance to elevated temperatures, oils and many hydrocarbons compared with conventional NBR. The seal is identified with BMW OE 11121265435, 11121285609 and Piaggio OE 829201.

Technical Specifications - CORTECO 12015381

Manufacturer: CORTECO
Part number: 12015381
Product type: Radial shaft oil seal / Simmerring
Design: BAVISLDRWX7
Material: FPM / FKM
Material type: Fluoroelastomer
Inside diameter d: 38 mm
Outside diameter D: 50 mm
Width B: 7 mm
Dimensions: 38x50x7 mm
Dust protection: Yes
Application: Engine shaft sealing
Vehicle manufacturers: BMW, Piaggio

BMW and Piaggio OE Reference Numbers

CORTECO 12015381 is associated with the following OE references:

BMW: 11121265435
BMW: 11121285609
PIAGGIO: 829201

These reference numbers are important when identifying the correct replacement seal for a specific engine application.

Compatibility should be confirmed using the OE number, vehicle model, engine version and installation position.

Dimensions of CORTECO 12015381

The principal installation dimensions are:

d: 38 mm
D: 50 mm
B: 7 mm

The seal is therefore designed for a nominal 38 mm shaft diameter, 50 mm housing bore and 7 mm installation width.

The dimensions should always be considered together with the FPM material, BAVISLDRWX7 construction and OE reference.

BAVISLDRWX7 Seal Design

The BAVISLDRWX7 designation identifies the specific construction of CORTECO 12015381.

In application-specific automotive shaft seals, the sealing lip geometry and additional design features can be engineered for a particular installation position and operating environment.

For this reason, a generic 38x50x7 mm oil seal should not automatically be considered technically equivalent to CORTECO 12015381.

Correct replacement identification should include:

CORTECO reference: 12015381
Design: BAVISLDRWX7
Material: FPM / FKM
Dimensions: 38x50x7 mm
Corresponding OE number: BMW or Piaggio

FPM/FKM Fluoroelastomer

CORTECO 12015381 is manufactured from FPM, a fluoroelastomer material also classified as FKM.

FPM/FKM is widely used for demanding automotive shaft seals because it provides good resistance to many:

• engine oils
• mineral oils
• synthetic lubricants
• fuels
• hydrocarbons
• elevated temperatures
• ageing and oxidation

These properties make fluoroelastomers particularly useful in engine and drivetrain sealing positions where operating temperatures can exceed the practical range of standard NBR compounds.

Actual compatibility should always be verified for the specific lubricant, additives and operating temperature.

Engine Shaft Sealing Function

CORTECO 12015381 provides dynamic sealing between a rotating engine shaft and a stationary housing.

The primary sealing lip operates directly against the shaft surface and helps retain lubricant within the mechanical assembly.

Its main functions include:

• retaining engine oil
• reducing lubricant leakage along the shaft
• maintaining controlled lubrication conditions
• separating the lubricated mechanism from its surroundings
• protecting the sealing interface
• supporting reliable operation of the rotating assembly

Correct performance also depends on shaft surface condition, alignment, installation accuracy, rotational speed and temperature.

Additional Protection Against Contamination

The seal incorporates additional protection for the working sealing area.

This helps reduce the ingress of external contaminants toward the primary shaft contact zone.

Protecting the sealing interface is important because dust and abrasive particles can accelerate wear of both the sealing lip and the shaft surface.

This feature is particularly useful in automotive applications exposed to changing environmental and operating conditions.

CORTECO 12015381 for BMW

CORTECO 12015381 is identified with two BMW OE references:

BMW 11121265435
BMW 11121285609

When searching for a replacement, these numbers can be used together with CORTECO 12015381 and the 38x50x7 mm dimensions.

Fitment should still be confirmed for the exact vehicle and engine version before installation.

CORTECO 12015381 for Piaggio

The corresponding Piaggio OE reference is:

PIAGGIO 829201

This reference provides an additional identification path for applications where the original Piaggio seal is being replaced.

The OE number should be checked against the original component or vehicle parts catalogue.

Why FKM is Used for Engine Oil Seals

The sealing lip of an engine shaft seal operates under demanding conditions.

Rotation generates frictional heat at the lip contact zone, while the elastomer is simultaneously exposed to hot lubricant and temperature cycles.

FKM is therefore selected for many engine sealing positions because it combines:

• thermal resistance
• oil resistance
• ageing resistance
• chemical stability
• suitability for demanding dynamic sealing environments

This material specification is an important part of CORTECO 12015381 and should be retained when selecting a replacement.

Replacement Selection for CORTECO 12015381

Before installing a replacement, verify:

Manufacturer: CORTECO
Part number: 12015381
Dimensions: 38x50x7 mm
Material: FPM / FKM
Design: BAVISLDRWX7
Application: Engine shaft
BMW OE: 11121265435 / 11121285609
Piaggio OE: 829201

A standard NBR 38x50x7 mm oil seal should not automatically replace this FPM version.

Although the installation dimensions may be identical, NBR and FKM differ in temperature capability, chemical resistance and ageing characteristics.

Operational Advantages

FPM/FKM material: suitable for demanding oil sealing environments and elevated temperatures.

38x50x7 mm dimensions: precisely defined installation geometry.

BAVISLDRWX7 construction: application-specific CORTECO shaft seal design.

Contamination protection: helps protect the primary sealing interface against external particles.

Engine application: designed for dynamic sealing around a rotating engine shaft.

OE identification: BMW and Piaggio reference numbers support accurate replacement selection.

FAQ - CORTECO 12015381

What are the dimensions of CORTECO 12015381?
The seal measures 38x50x7 mm, with a 38 mm inside diameter, 50 mm outside diameter and 7 mm width.

What material is CORTECO 12015381 made from?
The seal is manufactured from FPM/FKM fluoroelastomer.

What does BAVISLDRWX7 mean?
BAVISLDRWX7 is the construction designation for this specific CORTECO radial shaft seal. It should be considered together with the dimensions, material and OE references when selecting a replacement.

What is CORTECO 12015381 used for?
It is designed for specific engine shaft sealing applications in BMW and Piaggio vehicles.

Which BMW OE numbers correspond to CORTECO 12015381?
The BMW references are 11121265435 and 11121285609.

Which Piaggio OE number corresponds to CORTECO 12015381?
The Piaggio reference is 829201.

Are FPM and FKM the same material family?
Yes. Both designations refer to the fluoroelastomer material family, although they originate from different naming standards.

Is FKM suitable for engine oil?
FKM provides good resistance to many mineral and synthetic engine oils. Compatibility should nevertheless be verified for the specific lubricant and operating temperature.

Can an NBR 38x50x7 oil seal replace CORTECO 12015381?
Not automatically. The same dimensions do not guarantee equivalent performance. The original FPM material, BAVISLDRWX7 design and OE specification should be considered.