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
AI disclosure: this product description and its specifications were generated with AI assistance from the manufacturer's Illustrated Parts Catalog.
- Stock: Warehouse
- 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 only to customer-remorse returns and customer-initiated cancellations. If a problem is our fault (our cancellation, unavailability, wrong item, confirmed defect, or shipping damage) your refund is 100% with no fees.
- Return shipping: paid by buyer on customer-remorse returns; we pay return shipping when the problem is our fault.
- 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
We source products from manufacturers, authorized distributors, and established aviation suppliers as applicable. We are an independent reseller; we do not claim direct dealer or authorized-representative status for any brand. Documentation, source, and warranty eligibility vary by product and are confirmed 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.
