Service Bulletin

SB 663

Lycoming Engines

Issued: 2025-07-15
Revision: -
Document type: SB
Models covered: 0

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SB 663

Lycoming Engines

Issued 2025-07-15

Manufacturer - not an FAA rule

NOT AN FAA REQUIREMENT — This is a manufacturer document. It is not an FAA Airworthiness Directive and compliance is not required by 14 CFR 39 unless an AD cites it.

Non-Conforming Counterweight Bushings

Source: Lycoming Engines, retrieved 2026-09-01

View on Lycoming Engines' site

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