Overview
The Lycoming O-ring, P/N 74065, is a crucial sealing component designed to create a leak-proof interface for the oil level gauge within specified Lycoming reciprocating engines. This precision-engineered elastomeric seal ensures the integrity of the engine's lubrication system, preventing oil leaks at the point where the dipstick or oil level indicator enters the crankcase or oil sump. Its primary role is to maintain proper oil containment and prevent contamination, directly contributing to the reliable operation and safety of the aircraft engine.Specifications
The Lycoming P/N 74065 O-ring is engineered to meet specific dimensional and material requirements for its intended application. While exact dimensions are proprietary and best referenced in the official Lycoming Parts Catalog PC-115-2 for the O-540 series, the typical properties for an O-ring in this critical environment include:- Material: Generally manufactured from fluorocarbon elastomer (e.g., Viton) or nitrile rubber (Buna-N), chosen for its excellent resistance to petroleum-based oils, fuels, and hydraulic fluids, as well as high temperatures commonly encountered in engine compartments.
- Durometer: Typically in the range of 70 to 90 Shore A, providing a
- Stock: Out of Stock - On Backorder
- Manufacturer Part #: 74065
- Part#: 74065
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Returns & refund summary
- 30-day return window — with prior return authorization, unopened in original packaging.
- Restocking fee: 20% on unopened items, 30% on open-box items.
- Refund processing fee: 5.51% applies to all refunds (returns, cancellations, core-fee refunds) regardless of reason.
- Return shipping: paid by buyer.
- Non-returnable categories: installed/used parts, special-order or rebuilt items, programmed items (incl. ELTs), batteries, AOG-priority orders, international orders.
Full terms: Return Policy.
Authenticity & authorization
All parts sold by American Aviation Parts are genuine factory products sourced through authorized distribution channels. Our authorization status varies by brand — for some brands we are a direct authorized dealer; for others we are an independent reseller through authorized distribution. Either way, the part you receive is the same factory product, with standard documentation available on request.
See our full Manufacturer Authorizations page for the current per-brand status.
Need traceability paperwork?
If your installation requires FAA Form 8130-3, manufacturer Certificate of Conformance, or other traceability documentation, please call 1-877-722-8727 or email [email protected] before placing the order so we can confirm what is available for this part.
Shipping
Standard ground, expedited, and AOG shipping options are available at checkout. Full shipping-cost tiers and timelines are published on our Delivery Information page.
