SDR 99ZZZX425

Service difficulty report · Housing · Boeing 737*

Difficulty date
April 22, 1998
Submitted
March 26, 2000
Operation
General aviation
Make and model
Boeing 737*
Part
Housing
Part number
654458211
Condition
Cracked
Location
Hyd Mod Package
Component
65445815
Stage of operation
IN
Nature of condition
K
Precautionary procedure
K

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

What was found

SHUT-OFF VALVE MODULAR PACKAGE ASSY, P/N 65-44581-5, RECEIVED FOR O/H. UNIT REMOVED BECAUSE VALVE WAS LEAKING. AFTER REMOVAL OF TWO SHUT-OFF VALVES, A 1.75 INCH CRACK WAS FOUND IN HOUSING, P/N 65-44582-11. THE CRACK PROGRESSED FAR ENOUGH TO ALLOW FLUID TO LEAK FROM THE TOP OF THE VALVES. CRACK IS 1.75 INCHES LONG AND GOES COMPLETELY THROUGH THE .50 INCH THICK INTERNAL WALL OF THE HOUSING BETWEEN THE SHUT-OFF VALVES. COMPONENT IS NOT SUBJECTED TO EXTERNAL LOADS AND CRACK DOES NOT START AT A STRESS RISER. SUBMITTER STATED THIS IS SECOND HOUSING FOUND CRACKED IN THIS AREA. FIRST CRACK SHORTER AND WAS A STRAIGHT LINE. THIS CRACK IS JAGGED AND APPEARS TO FOLLOW THE GRAIN STRUCTURE. REF: OHM CH 32-43-22.