Aftermarket Bosch Alternator Rebuild Kit 20021RK

INCLUDED IN REBUILD KIT:

Bearing DE
Bearing SRE
Brushes
Rectifier
Slip Ring
Tolerance Ring
Voltage Regulator 

NOT INCLUDED IN REBUILD KIT: 

Cover
Nut 1
Nut 2
Pulley Nut
Rectifier Cover

Specifications

Features & Benefits

• Complete aftermarket rebuild solution for compatible alternators

• Includes essential replacement components for alternator rebuilding and repair

• Helps restore proper charging system performance

• Helps replace common internal wear components during a complete rebuild

• Manufactured for dependable fit, performance, and long service life

• Ideal for professional rebuilders, automotive repair shops, and DIY technicians

• Convenient alternative to sourcing individual rebuild components separately

• Cross-referenced to OEM and aftermarket alternator part numbers for easier identification

What Does an Alternator Rebuild Kit Do?

An alternator rebuild kit provides a selection of replacement components commonly needed to service and rebuild a worn or failed alternator. Depending on the specific kit, components may include bearings, brushes, brush holders, slip rings, rectifiers, voltage regulators, and other service parts required for the applicable alternator design.

Rebuilding an alternator allows worn internal components to be replaced while retaining serviceable major components such as the rotor, stator, housing, and pulley when they remain within specification. A properly rebuilt alternator can help restore reliable charging output, smooth mechanical operation, and dependable electrical system performance.

Always review the Kit Contents for the specific rebuild kit before ordering, as included components vary by alternator application.

Common Signs an Alternator May Need Rebuilding

Consider rebuilding or servicing the alternator if you notice:

• Battery warning light illuminated

• Low or inconsistent charging voltage

• Battery not charging properly

• Intermittent charging system operation

• Grinding, whining, or bearing noise

• Worn brushes or slip rings

• Failed voltage regulator or rectifier

• Excessive bearing play or roughness

• Internal component wear discovered during alternator inspection or testing

Installation Recommendations

Installation should be performed by a qualified technician or experienced alternator rebuilder. Before rebuilding the alternator, completely disassemble and inspect the unit for worn, damaged, overheated, or contaminated components.

Inspect the rotor, stator, slip rings, bearings, rectifier, voltage regulator, brushes, brush holder, pulley, housing, terminals, insulators, wiring, and fasteners as applicable to the alternator design.

Always verify the Lester number, OEM alternator number, alternator series, specifications, and product photos before ordering. After reassembly, bench-test the alternator to verify proper charging output and overall operation before returning it to service.

While You're Rebuilding

Depending on the contents of your rebuild kit and the condition of the alternator, inspect other components that may require replacement:

• Bearings

• Brushes

• Brush Holder

• Slip Rings

• Rectifier

• Diodes

• Rotor

• Clutch Pulley

• Insulators

Important: Rebuild kit contents vary by application. This kit includes only the components specifically listed in the product description. Components listed above are inspection recommendations and are not necessarily included with the rebuild kit.

Why Buy From RC Auto Electric?

RC Auto Electric specializes in alternator and starter rebuilding components for professional rebuilders, repair shops, automotive technicians, and DIY enthusiasts. Our extensive catalog includes thousands of OEM and aftermarket electrical components backed by accurate cross-reference information to help simplify part identification and reduce ordering mistakes.

Disclaimer

Compatibility information is provided as a reference only. Manufacturing revisions, production changes, and previous rebuilding modifications may affect alternator components and rebuild kit compatibility. Always compare the Lester number, OEM alternator number, alternator series, specifications, included components, cross-reference numbers, and product photographs before ordering.

This rebuild kit includes only the components specifically listed in the product description. If you are unsure about compatibility or kit contents, contact RC Auto Electric before ordering.