Service difficulty report · Spring · Boeing 737*

Difficulty date
June 15, 2023
Submitted
October 20, 2023
Operation
General aviation
Make and model
Boeing 737*
Part
Spring
Part number
31690971
Condition
Wrong Part
Location
Regulator Valve
Stage of operation
NR
How discovered
9
Nature of condition
W
Precautionary procedure
O

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

What was found

DURING COMPONENT OVERHAUL FOKKER SERVICES AMERICAS INADVERTENTLY BUILT AND RETURNED TO SERVICE SIX (6) HIGH SIEGE REGULATOR VALVES PN 107484-7 WITH SPRINGS INTENDED FOR THE PRE.SB VALVO. THE INCORRECT SPRING PN 316097-1 (CMM IPL FIG-ITEM 3-90)WAS INSTALLED RATHER LHAN PN 3174867-1 (FIG-ITEM 3-90A) WHLC/I IS THE CORRECT SPRING FOR THE 107484-7 CONFIGURATION. ALLHOUGH ALL OF THE AFFECTED UNITS WERE TESTED AND MEL ALL CMM TEST REQUIREMEN1S PRIOR TO RELUM TO SERVICE, WE RECOGNIZE THAT LHLS INCORRECT CONFIGURATION COULD PER SB 107484-36-1453 COULD LEAD TO REDUCED COMPONENT RELIABILITY . OUR INITLAL REVIEW INDICATES THAL LHE INCORRECT SPRING WAS ORDERED DUE TO ONLY THE INCORRECT SPRING BEING LISTED IN THO BILL OF MATERIALS AND THE TECHNICIAN ACCEPTING 1HE INFORMATION AS CORRECT WITHOUT VERIFYING EFFECTTIVITY IN THE CMM.