Futaba S3117/S3157 Servo Internal Gear Set for Repair - FUAS3274  [FUAS3274]

Service-grade gear replacement for S3117/S3157

This gear set is an RC-scale replacement pack designed for Futaba-listed servo models S3117 and S3157 and the associated internal gear assemblies referenced by AS3274 and EBS3358 codes. It restores internal gear geometry and mesh after wear, helping to maintain expected servo performance in model applications.

Fit this set when a servo shows play, inconsistent centring, or intermittent gear noise caused by worn or stripped teeth. The parts are supplied as a direct internal gear replacement set matching the original gear train layout referenced in the product identifiers.

Installation notes and tuning role:

• Verify the servo model codes printed on the case match the S3117 or S3157 listing before disassembly.
• Remove the servo cover and lay the existing gear stack beside the replacement set to confirm orientation and order.
• After fitting the new gears, rotate the output spline by hand to check mesh and free movement before restoring power or reattaching linkages.
• Use incremental trim and endpoint checks on your radio to confirm restored centring and travel; re-check for unusual noises under light load.