As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING A PHASE INSPECTION OF THE FUEL LOW LEVEL SWITCH, THE SWITCH WAS FOUND FAULTY. DURING REPLACEMENT, IT WAS NOTICED THERE WAS ONLY ONE NUT HOLDING THE SWITCH IN PLACE. (NO JAM NUT). THE IPC CHAPTER 28-40-01 FIG 1 ITEM 6 SHOWS TWO NUTS. TWO OTHER AIRCRAFT, S/N'S 550-663 AND 550-666, WERE ALSO FOUND TO BE IN THE SAME CONDITION. SUBMITTER STATED THERE IS NO WAY TO SAFETY JUST ONE NUT. THE SITUATION COULD POSSIBLY CAUSE A FUEL LEAK. (X)