What was found
LEFT FMC FAILED MOMENTARILY DURING DEPARTURE, SELF RESTORE AFTER 30 SEC. LEFT FMC FAILED APPROXIMATELY 4 HRS INTO FLIGHT AND RESTORED AFTER FOLLOWING QRH. LEFT FMC FAILURE AGAIN ABOUT 3 MIN AFTER PREVIOUS AND WE RAN FMC BOTH ON RT FOR REMAINDER OF FLIGHT WITH NO ISSUES. ACFT GROUNDED. ACCOMPLISHED FMC SOFTWARE CONFIGURATION CHECK REF AMM 34-61-00-750-801. SOFTWARE IS UP TO DATE. ACCOMPLISHED FMCS PERFORMANCE FACTORS TEST REF AMM 34-61-00-800-801. ALL PARAMETERS ARE CORRECT. ACCOMPLISHED FMCS OPS TEST REF AMM 34-61-00-710-801. OPS CK GOOD. ACCOMPLISHED LRU REPLACEMENT TEST FOR FMC REF FIM 22-11, TASK 802. ALL TESTS PASSED. THIS CLEARS MEL 34-36J.