Collection: Pulleys

Alternator pulleys: adapting engine drive

The alternator pulley transfers belt force between the engine and the alternator. Its diameter, number of grooves, and alignment directly affect alternator RPM, slip risk, belt wear, and load stability.

Diameter and alternator RPM

The pulley diameter changes the transmission ratio. A smaller pulley increases alternator RPM at equal engine RPM; a larger pulley reduces it. The Multi-groove pulley (8) Ø 48.1 mm and the Multi-groove pulley (8) Ø 56 mm suit different setups depending on the engine pulley, available space, and target RPM.

Number of grooves and belt grip

Multi-groove pulleys increase contact surface with the belt and reduce slip, especially on high-power alternators. The Multi-groove pulley (6) for Alpha 24/110 and Alpha 24/150 fits mounts compatible with these alternators, while 8-groove versions suit belts and drives designed for this profile.

Mounting checkpoints

Before replacement, check belt type, number of grooves, diameter, bore, alignment with the engine pulley, and space around the alternator. Poor compatibility can cause noise, overheating, premature wear, or reduced output.

Building the complete system

Pulleys are part of the engine power generation assembly. To complete the installation, also see the alternators, alternator accessories, power generation, and electricity collections.