Alternator & Regulator: Description

All General Motors vehicles, except Chevette and 1000 Diesel, use the Delcotron alternators, available with different idle outputs and maximum outputs of 42 (10SI), 56 (12SI), 63 (10SI), 66 (12SI), 70 (15SI), 78 (12SI), 85 (15SI) and 100 (27SI) amps.

Fig 1: View of Delcotron 10 SI Alternator with Integral Regulator

All models feature a solid state regulator mounted inside the alternator, providing electrical system protection, eliminating needless wiring, saving space and preventing misconnection of terminals.

The construction and operation of all models is basically the same. Delcotron alternators consist primarily of 2 end frame assemblies, rotor, stator, brushes, slip rings and diodes. The rotor is supported in the drive end frame by ball bearings and in the slip ring end frame by roller bearings. Bearings are sealed and do not require periodic lubrication.