Service difficulty report · O-Ring · Boeing 737924ER

Difficulty date
April 14, 2026
Submitted
April 22, 2026
Operation
Air carrier
Aircraft
N75425
Make and model
Boeing 737924ER
Aircraft serial
33460
Aircraft time
55,141 hours, 19,722 cycles
Engine
Cfmint CFM567B263
Part
O-Ring
Part number
6493970030
Condition
Damaged
Location
Nr 1 Engine
Stage of operation
CL
How discovered
O
Nature of condition
K, B
Precautionary procedure
A

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

What was found

AFTER TAKEOFF STRONG SMELL OF SOMETHING BURNING FROM THE FLIGHT DECK TO THE AFT GALLEY.SMOKE / ODOR IN THE PLANE QUESTIONAIRE PHOTO UPDATE VERBAL UPDATE FROM FLIGHT CREW: SMELLED SMOKE ON ROLL OUT, FLIGHT ATTENDANTS SAID IT WASNT OVENS, SMELL DISAPEARED AFTER 5000 FT, NEVER SAW SMOKE. LOCKED LP. PLEASE PERFORM SMOKE/ODOR IN THE FLIGHT DECK/CABIN - CONDITIONAL INSPECTION PER AMM 05-51-26-800-801-C1. TAGGED SDR PERFORMED INSPECTION IN REF TO AMM 05-51-26-800-801-C1 STEP E WITH NO SMELL NOTED. RAN BOTH ENGINES. AFTER STARTING NUMBER ONE ENGINE WITH NUMBER 2 RUNNING SMOKE SMELL FILLED CABIN IMMEDIATLEY. ENGINE BLEEDS OFF, APU BLEED ON AND BOTH PACKS WERE OFF. SMELL GOES AWAY AFTER 5 MINUTES. ITS AN OIL SMELL. REF FAULT ISOLATION MANUAL 71-05 TASK 807 FUMES OR SMOKE IN CABIN; PNEUMATIC POWER SUPPLIED BY ENGINE. ISSUE DOES NOT PERTAIN TO PACKS RUNNING GO TO STEP 6. WE REALIZED THIS WAS THE AIRPLANE WITH THE TAR FOD AND SUSPECT INGESTION IN NUMBER 1 ENGINE DUE TO SMELL IN CABIN. SMELL ONLY COMES FROM ENGINE 1 WITH ALL PACKS OFF. RAN BOTH ENGINES FOR 40 MIN BLEEDS ON PACKS ON SMELL STRONGEST AFTER ENG START THEN FADES,RESTARTED BOTH ENGINES 3 TIMES SAME RESULTS WORKED IN CONJUNCTION WITH LP8554982. AFTER FILTER REPLACMENT, STARTED #1 ENGINE FIRST WITH NO ODORS. THEN STARTFOUND THE NUMBER 1 LP SHAFT SEALS DETERIORATED ALLOWING OIL TO POOL BEHIND THE SPINNER. SEE LOG PAGE 8583083 FOR CORRECTIVE ACTION AND LOG PAGE 8627362 FOR THE SUBSEQUENT OPERATIONAL TESTS. THIS LOG PAGE IS CLEARED