Service difficulty report · Fmu · Boeing 777222

Difficulty date
November 27, 2012
Submitted
December 3, 2012
Operation
Air carrier
Aircraft
N786UA
Make and model
Boeing 777222
Aircraft serial
26938
Aircraft time
68,975 hours, 9,911 cycles
Engine
Pwa PW40903
Part
Fmu
Part number
8088001
Part serial
106
Condition
Faulty
Location
Nr 1 Engine
Stage of operation
IN
How discovered
O
Nature of condition
J
Precautionary procedure
O

As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.

What was found

LCL MAINT REPORTED: DURING L FUEL VAL E MSG T-SHOOTING, AT ENGINE START GOT START VALVE MSG. PLEASE IDENTIFY WHAT WAS THE MAINT MESSAGE FOR START VALVE PROBLEM, PROBLEM MAY BE RELATED TO W0629 PCN 566-0059 & W0625 PCN 566-0181 WIRE HARNESSES. (REF EM3684, EM3685, EM3687 FOR L FUEL VALVE MSG T -SHOOTING). REPLACED FMU PER MM. REPLACED WIRING HARNESSES WO629 AND WO625, ENGINE RUN PER JRH OPS AND LEAK CHECK OK. BOTH RELAYS K76104 AND K76107 WERE REPLACED. DURING ENGINE RUN LEFT ENG START VALVE DID NOT OPEN AUTOMATICALLY. MANUALLY OPENED THE START VALVE AND RAN THE ENGINE BUT AFTER ENGINE SHUT DOWN WE HAD THE SAME SITUATION AS WHEN THE AC ARRIVED AT THE GATE. REPLACED START VALVE PER MM. OPS & LEAK CHECK OKAY.