What was found
#1 ENGINE TREND DATA SHOWS A SHIFT IN DEGT, HDM, DELTA FUEL FLOW, DELTA CORE SPEED AND VSV POSITION DIVERGENCE WITH EXCESSIVE VSV SCATTER. (#PRI1/ETOPS)SEA ONLY. GROUNDED - YES. REMOVED BORESCOPE PLUGS 2 THROUGH 9, BORO PLUG 13,15 AND 17. REMOVED DRIVE PAD COVER. COMPLETED STEP 1 IAW TC 78472018, STEP 2 I/W TC 78472020 STEP 3 I/W T/C 78472022. FOUND 12 HPT BLADES WITH SIGNS OF DISTORTION AND MELTING NOT PERMITTED STEP 3B(1)(J) 78643 INSPECTOR #11. INSTALLED DRIVE PAD COVER PER B737-800 AMM 72-63-01-400-801-F00. NOTE LEAK CK REQ. INSTALLED BORESCOPE PLUGS 2-9, 13, 15 AND 17 REF MM 72-00-00-200-817-F00. ENG REMOVED & REPLACED REF T/C 78471000 & 78471001. LEAK CHECK OF DRIVE PAD ACCOMPLISHED AFTER SHOP VISIT.