What was found
DURING CLIMB AFTER CENTER TANK WAS EMPTY, THE RIGHT FUEL PRESSURE LOW LIGHT ILLUMINATED. RIGHT FUEL INDICATION DID NOT DECREASE AND THE LEFT FUEL INDICATION WAS DECREASING AT THE RATE OF EQUAL TO BOTH ENGINE BURNS. ACCOMPLISHED COCKPIT OPERATING MANUAL PROCEDURES AND FUEL LOW PRESSURE LIGHT EXTINGUISHED WITH CROSSFEED ON. FLIGHT RETURNED TO PHX AND LANDED WITHOUT INCIDENT. RIGHT FUEL INDICATION DID DECREASE ON DESCENT. REPLACED O-RING AT RIGHT AFT FUEL BOOST PUMP PRESSURE LINE. ALSO, REPLACED THE LEFT ENGINE LOW PRESSURE FUEL FILTERS. OPERATIONAL CHECK NORMAL AND AIRCRAFT RETURNED TO SERVICE.