What was found
RIGHT ENGINE BLEED VALVE WON’T OPEN, NO AIRFLOW, "RT ENG BLEED" LIGHT ILLUMINATED, AIRCRAFT BACK TO BLOCK AND GROUNDED BY MAINTENANCE. FOUND RIGHT ENGINE PRV STUCK IN THE CLOSED POSITION, FAILED THUMB TEST. SWAPPED RT PRV AND HPSOV IAW B767 AMM 36-11-18. TRANSFERRED RT ENGINE PRV SYSTEMS IN THE INOPERATIVE OPEN POSITION TO DI IAW MEL 36-11-8-1-1A. ACCOMPLISHED MEL PM 36-11-8-3,78-31-1,36-12-2 AND 36-11-2. A/C RELEASED CAT IIIA, REALM PLACARD ROTATED. A/C DOWNGRADES TO ETOPS 120. LP 38152-07/1