Service difficulty report · Nut

Difficulty date
January 3, 2025
Submitted
January 3, 2025
Operation
General aviation
Engine
Lyc IO360L2A
Part
Nut
Part number
SL12186
Condition
Damaged
Location
Engine
Stage of operation
IN
How discovered
V
Nature of condition
O
Precautionary procedure
K

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

NHDO ASSEMBLING COMCC??NG RODS TO CRANKSHAFT DURING OVERHAUL. II WAS NOTICED THAT T NUT WAS NOT SLMNG FLUSH TO ITS BEARING SURFACE. THE NUT HAD BEEN RUN DOWN FINGER TIGHT, PRIOR TO TORQUING LOOKING AT THO NUT, 1T IS OBVIOUS THAT THO NUT WAS NOT 1N THE PROPER ONCNTABON WHEN THE TREADS WERE CUT LOOKING AT LHE NUT BEING THREADED ON A BOLL ILLE WOOOTO 1$ OBVIOUS THE DISTON,ON CAN BE SOON ,WE BOLLOVE THAT THO NUT COULD HAVE BOON PROPE??Y TORQUED AND MAY HAVE WORKED SATISFACTORILY. BUT THERE ,S ALSO THO PROBABLY THAT WOULD HAVE BEEN UNDUE STRESSES ON THO NUT WT.CH WOULD HAVE RESULTED RN 11< !ALLURE AND POSSIBLE CORASTRCPT,C FAILURE OF THE ENGINE THIS DISCREPANCY WAS NOT SEEN IN THE OTHER PARTS ON IHE OOREH WE RECEIVED.