What was found
DURING CRUISE FLT LVL 320 SECONDARY ENGINE INDICATIONS APPEARED. INVERSE READING OF 4.0 ON LH ENG N1 VIBRATION. REPEATED SEVERAL TIMES(<P>PERFORMED #1 ENG BALANCE SOLUTION IAW B777 AMM 71-00-00 TEST 12B, ALL WEIGHTS IN SPINNER SHOW POSITION 1. MAT SOLUTION SHOWS CHANGE WEIGHT POSITION 20, 28, 29, AND 37 TO ALL P12 WEIGHTS. INSTALLED WEIGHTS IN POSITIONS LISTED . AFTER CHANGING WEIGHTS TO MAT SOLUTION WEIGHTS. PERFORMED LOW PRESS SYS VIBE SURVEY IAW B777 AMM 71-00-00 TEST 10, ENGINE WITHIN LIMITS </P>)