LW-11750 – Lycoming Engines OEM Connecting Rod
Available now through the AirParts Aero marketplace.
Overview Section
The Lycoming LW-11750 is a genuine OEM (Original Equipment Manufacturer) connecting rod designed for a wide array of high-performance 4-cylinder (360 series) and 6-cylinder (540 series) engines. As a critical reciprocating component, the connecting rod acts as the mechanical link between the piston and the crankshaft, converting the linear energy of combustion into rotational torque.1
This specific part number is engineered to meet the demanding stresses of both naturally aspirated and turbocharged environments, including aerobatic (AEIO) and high-altitude (TIO) configurations. Lycoming’s manufacturing process involves precision forging and rigorous non-destructive testing (NDT) to ensure the rod can withstand millions of cycles under high-pressure combustion loads.
Key Features Section
High-Strength Forged Steel: Precision-forged to provide maximum grain flow integrity, ensuring the rod can handle the massive tensile and compressive forces of high-RPM flight.
Balanced Construction: Manufactured to strict weight-matching tolerances to minimize engine vibration and extend the life of the crankshaft main bearings.
Bushed Small End: Features a high-quality bronze bushing at the piston pin end, designed for optimal lubrication and wear resistance.
Precision Machined Big End: The crankpin end is machined to exact tolerances to ensure a perfect fit for the rod bearings, maintaining the critical oil film required during high-power operations.
Broad Engine Compatibility: Approved for use in 360 and 540 series engines, including specialized AEIO aerobatic and TIO turbocharged models.
OEM Reliability: Meets the original FAA Type Certificate requirements, ensuring airworthiness and predictable service life compared to non-certified aftermarket alternatives.
Technical Specifications Section
| Specification | Detail |
| Part Number | LW-11750 |
| Manufacturer | Lycoming Engines |
| Material | Forged Alloy Steel |
| Application | Reciprocating Engine (360 & 540 Series) |
| End Style | Bushed Piston End / Split Crankshaft End |
| Included Hardware | Rod Cap (Check for Bolts/Nuts per specific kit) |
| Certification | FAA-PMA / OEM |
Engine Compatibility Section
The LW-11750 is one of the most versatile connecting rods in the Lycoming catalog:
360 Series: O-360, LO-360, IO-360, AEIO-360, TO-360, and TIO-360.
540 Series: O-540, IO-540, AEIO-540, TO-540, and TIO-540.
Aircraft Platforms: Found in everything from the Cessna 172/182 and Piper Archer/Saratoga to high-performance aerobatic platforms like the Extra 300.
Technical Applications & Safety
The connecting rod is subjected to alternating tension and compression. Any surface imperfection or incorrect assembly can lead to catastrophic engine failure.
Safety Warning: Installation and Fasteners. Connecting rod bolts and nuts are "life-limited" or "single-use" in many Lycoming service instructions. When installing the LW-11750, you must use new, high-strength bolts and nuts and follow the stretch-method or specific torque-plus-turn requirements found in the Lycoming Overhaul Manual.
Weight Matching: If replacing a single rod, it must be weight-matched to the other rods in the engine to prevent harmonic imbalances that can lead to crankshaft failure. Lycoming rods are typically marked with a weight code; ensure the new rod matches the existing set's weight category.
Installation & Maintenance Addendum
Bearing Fit: Always check the "Big End" bore for roundness and size before installing bearings. Even a new rod should be verified against the overhaul manual specifications.
Piston Pin Fit: Verify that the piston pin slides through the small-end bushing with the correct "thumb-press" fit. If the bushing is too tight, it must be honed to the proper clearance.
Orientation: Connecting rods must be installed in the correct orientation (usually with the "numbers" or "tang slots" facing a specific direction toward the camshaft or oil sump) to ensure proper lubrication of the cylinder walls and wrist pins.
Fits On The Following Engines:
- O-360-A1A, A1AD, A1C, A1D, A1F6, A1F6D, A1G6, A1G6D, A1LD, A2A, A2D, A2E, A2F, A2G, A3A, A3AD, A4A, A4G, A4J, A4K, A4M, A5AD, B2A, C1A, C1C, C1E, C1F, C2A, C2C, C2D, C2E, D2A, D2B, F1A6
- LO-360-A1G6D
- IO-360-B1A, B1B, B1D, B1E, B1F, B2F, B2F6, B4A
- AEIO-360-B1G6, H1A
- HO-360-B1A, B1B
- TO-360-C1A6D
- O-540-A1A, A1A5, A1B5, A1C5, A1D, A1D5, A2B, A3D5, B1A5, B1B5, B2B5, B2C5, B4B5, E4A5, E4B5, E4C5, G1A5, G2A5, H1B5D, H2B5D
- IO-540-C4B5, D4A5, G1D5, T4A5D, T4B5D
- TIO-540-C1A, E1A, G1A, H1A