SB 659

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Lycoming Engines

Issued 2025-02-21

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.

STD-33 Plain Washer Replacement

Source: Lycoming Engines, retrieved 2026-09-01

View on Lycoming Engines' site

Applies to 8 models in our index

Lycoming IO-390 Lycoming Engines · engine
Lycoming IO-580 Lycoming Engines · engine
Lycoming IO-720 Lycoming Engines · engine
Lycoming O-235 Lycoming Engines · engine
Lycoming O-320 Lycoming Engines · engine
Lycoming O-360 Lycoming Engines · engine
Lycoming O-435 Lycoming Engines · engine
Lycoming O-540 Lycoming Engines · engine