What was found
TE FLAP DISAGREE WHEN GOING TO FLAPS 25. COMPLETED QRH 9.1.17 LANDED FLAPS 20 ***EMERGENCY DECLARED*** ENT BY:5190314 RPT BY:5190314 R/I 12JUL23 22:37 MEM U REASON CODE : PREMATURE REMOVAL/INSTALLATION OFF MPN: 7820924 CPN: 2717624 POS: ONL ON MPN: 7821344 SRL: 5910 TAG NBR: 00I930 FACT 12JUL23 22:37 MEM U TSM: 27-51-00 AMM: 27-51-11-4 WHILE TROUBLESHOOTING THE FLAP WITH FIM 27-51 FT 808 FIG 105 FOUND INDICATOR TRIPPED ON LH #4 FLAP TRANSMISSION AND NOTICED THAT THE BALL SCREW THREADS WAS JAGGED AND WORN AND BALL NUT WAS FULL OF WATER. REMOVED AND REPLACED #4 LH BALL SCREW. OPS CHECKS GOOD. RESET TRANSMISSION INDICATOR. BALLSCREW NEW PN/ 7821344 SN/5910. OLD PART, THE TAG WAS DAMAGED AND ILLEGIBLE.