S3107 Servo Case Set Replacement - Futaba FUAS4122  [FUAS4122]

Replacement Servo Shell

This Futaba FUAS4122 servo case set is a direct-fit service replacement made specifically for the S3107 series servo. Supplied without retail packing, the kit contains the external housing parts required to replace a damaged shell while keeping the original internal components intact.

Use this case set when the existing shell has cracks, stripped mounting points, or alignment issues that interfere with servo installation. The part keeps factory mounting geometry and internal clearances so mounting holes, spline alignment and connector access match the original S3107 configuration.

Installation overview: remove the servo cover and note gear, shim and connector positions; transfer the internal gear stack and PCB into the new case; secure internal fasteners and confirm spline alignment before reinstalling into the model. After reassembly, check neutral position and endpoint behavior on your transmitter to confirm calibration remains correct.

Practical maintenance role: swapping a damaged case restores repeatable mounting and servo geometry, helping preserve steering and control precision during setup and testing without altering the servo internals.