As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
THE OVERHAUL PROCESS OF GEARSHAFT PN 310045001 INCLUDES REMOVING THE WORN SPLINES OF THE INPUT PORTION OF THE GEAR AND WELDING ON A NEW SPLINE SECTION. IN THIS CASE THE TEETH OF THE NEW SPLINE SECTION ARE SLIGHTLY UNDERSIZED NOT ALLOWING THE GEAR TO MESH WITH A NEW SPLINED QUILL SHAFT USED TO DRIVE THE COMPRESSOR OF THE A/C UNIT. THIS SPECIFIC GEARSHAFT IS LOCATED ON THE LOW SPEED PAD OF THE ACCY GEARBOX. (K)