Alpha Aviation’s 3-Stone Rotary Cylinder Hone Kit makes available a tool to recondition the interior running surface of the oleo cylinder barrel for certain Ercoupe models.
According to company officials, it is intended to be used each time the MLG oleo struts are disassembled for routine seal replacement or when upgrading to the company’s Main Landing Gear Oleo Restoration Kit.

The clean and resurfaced interior cylinder bore results in increased seal effectiveness and service life and can be accomplished with or without removing the Taxi Stack end fitting and donuts, company officials explain.
This kit is applicable to Ercoupe 415-C, CD, D, E, G, F-1, F-1A, Alon A2, A2-A and early M10 aircraft that are equipped with either the Hayes welded or Erco forged trailing link MLG assemblies that incorporate liquid filled oleo struts.
The kit, priced at $39 plus shipping, includes:
- Rotary Cylinder Hone (1)
- Cylinder Hone Extension (1)
- Course Grit 080 Stones (3)
- Medium Grit 220 Stones (3)
- Finishing Grit 320 Stones (3)
- Cotter Pins (9)
- Hex Key (1)
- Storage Pouch (1)