UPDATE 1-BP Carson CA refinery FCC restart by July 31-sources

(Adds BP no comment, notices filed, details.)

HOUSTON, July 17 (Reuters) - The restart of the 102,500 barrel-per-day gasoline-producing fluidic catalytic cracking unit and ancillary units at BP Plc's (BP.L)(BP.N) 265,000-bpd Carson, California refinery is expected to finish by July 31, according to sources familiar with refinery operations.

When the Los Angeles-area refinery's FCC was shut during the weekend of July 11-12, sources said the unplanned repairs were expected to last about a week.

A BP spokesman declined to discuss operations at the Carson refinery.

BP has filed notices with California pollution regulators warning of planned flaring at the Carson refinery between Friday and July 31.

The FCC had problems with a power recovery turbine, according to the sources. Other units that were shut are a hydrogen desulfurization unit, a catalytic reformer, an alkylation unit and an isomerization unit, all of which play roles in the production of gasoline. (Reporting by Erwin Seba; Editing by John Picinich)