20701801 S3 Crankshaft Flange for Volvo FH12

What does a crankshaft flange do?

The compressor crankshaft flange serves as a critical connecting element that links the air brake compressor's crankshaft to the engine drive. It performs the vital functions of centering, sealing, and load transfer between the compressor housing and the crankshaft. By providing a stable seat for bearings and seals on the drive side, this component ensures the drive mechanism—whether gear, pulley, or coupling driven—remains perfectly aligned during operation.

Compatible Volvo FH12 applications

This specific flange is engineered for Volvo FH12 trucks, including various power outputs such as the FH 12/340, FH 12/460, FH 12/380, FH 12/420, and FH 12/500. It is built using heavy-duty grade materials to withstand the high-pressure environments found in heavy commercial vehicle pneumatic systems.

Installation and maintenance guidance

When performing maintenance or repairs on the air brake compressor, technicians should verify the pilot diameter, bolt hole circle, and seal seat size to ensure exact fitment. Even a slight mismatch in flange thickness or hole count can lead to premature air leakage or excessive vibration within the compressor assembly.

Selection and troubleshooting

Selecting the correct component based on the compressor type or housing casting number is essential for reliable service. For professional installation, ensure all mating surfaces are clean to maintain the integrity of the seal seat and bearing seat.

OE cross-reference

13 01 13 (Compressor Crankshaft Flange) is the equivalent of the Volvo OE number. This part directly replaces Volvo OE number 20701801S3.