Komatsu Engine V-Belt Alternator Drive 04120-21732

Komatsu Engine V-Belt Alternator Drive 04120-21732 is a Komatsu engine replacement part listed by 19PARTS for engine-section lookup, hub navigation, and part-number verification.

Product overview

Part number 04120-21732 is listed as V-Belt Alternator Drive. Search also by the no-dash alternate number 0412021732.

Engine book references

This part appears in Komatsu engine parts book paths such as:

• ENGINES / S6D140-1U S/N 10001-UP / ELECTRICAL SYSTEM / ALTERNATOR AND MOUNTING (35A) (0601)
• ENGINES / S6D140-1U S/N 10001-UP / ELECTRICAL SYSTEM / ALTERNATOR AND MOUNTING (50A) (0602)
• ENGINES / S6D140-1U-F S/N 10001-UP / ENGINE / ALTERNATOR MOUNTING (35A)(#19053-) (A6010-A4B4)
• ENGINES / S6D140-1U-F S/N 10001-UP / ENGINE / ALTERNATOR MOUNTING (50A¤ 60A)(#19053-) (A6010-A4B3)
• ENGINES / S6D140-1U-F S/N 10001-UP / ENGINE / SPARE PARTS (EC NOISE SUPPRESSION SPEC.)(#19053-20046) (A9020-A4A4)
• ENGINES / S6D140-1U-F S/N 10001-UP / ENGINE / SPARE PARTS (EC NOISE SUPPRESSION SPEC.)(#20047-) (A9020-A4A4A)

This part appears in 10 Komatsu engine book paths in our reference data.

Verification note

Always confirm final fitment by engine model, serial range, diagram callout, and part number before ordering. Hub references are provided to help buyers find the right engine section and related parts faster.

Keep Ops Moving

19PARTS organizes Komatsu engine parts around searchable engine-model hubs so rebuild shops, equipment owners, and fleet teams can identify parts and keep repairs moving.