As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING TAXI OUT, UPON START ATTEMPT FOR LH ENG, ENG START VALVE WOULD NOT OPEN. AIRCRAFT RETURNED TO BLOCKS (BTB). DEFERRED LT ENG START VALVE PER MEL 80-00-2-1. PLACARDS INSTALLED. MBCB 02/09/26. REPLACED LT ENGINE START VALVE PER B767 AMM 80-11-02. SYSTEM CHECKS NORMAL. DI AND PLACARD REMOVED. NO MTC PROCEDURES APPLIED. AIRCRAFT RETURNED TO SERVICE.