Futaba FUAS4138 Servo Housing Kit for S3115 and S3116  [FUAS4138]

Servo housing replacement for S3115 and S3116

This Futaba FUAS4138 servo case set is intended as a direct replacement shell for Futaba S3115 and S3116 servos and is provided without retail packaging. The description concentrates on correct fitment and workshop use for hobby servos rather than claiming any changes to performance.

Scope of compatibility is confined to the S3115 and S3116 units specified; other Futaba models may use different screw patterns or internal arrangements. The replacement case is intended to correct damaged enclosures, realign internal elements, and secure the gear train and PCB during servicing operations.

Fitting guidance: take off the servo horn and outer case, mark gear orientation and PCB position, transfer internals into the new housing observing clearance and correct screw torque, then reassemble and verify travel and neutral position using your transmitter. Preserve any shims or bearings found in the original assembly to maintain gear alignment.

Service purpose: this case helps enable consistent reassembly and maintain mechanical alignment that supports smooth movement and precise feedback from the servo. It should be used as a maintenance part rather than presented as a performance enhancement.