Service difficulty report · Probe · Boeing 737890

Difficulty date
May 29, 2018
Submitted
May 31, 2018
Operation
Air carrier
Aircraft
N506AS
Make and model
Boeing 737890
Aircraft serial
35690
Aircraft time
37,955 hours, 11,635 cycles
Engine
Cfmint CFM567B27
Part
Probe
Part number
TC29604
Condition
Faulted
Location
Nr 1 Engine Egt
Stage of operation
TO
How discovered
O
Nature of condition
M, J
Precautionary procedure
O

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

What was found

THE #1 ENGINE EXPERIENCED AN EGT EXCEEDANCE DURING TAKEOFF THAT MAY HAVE EXCEEDED THE TRANSIENT AREA LIMITS. PEAK EGT RECORDED ON REPORT 06 WAS 976 DEGREES DURING TAKEOFF (FLIGHT PHASE 4.). ACFT GROUNDED. FOUND THE RED BOX AROUND EGT INDICATOR THE PEAK WAS 20 SECONDS AT 950 - 977.5 IAW AMM 71-00-00-740-8011-F00. PERFORMED A WIRE HARNESS RESISTANCE CHECK, FOUND VALUES TO BE WITHIN TOLERANCE IAW AMM 77-21-01. INTERROGATION OF FMC CDU SHOWS FAULT MESSAGE 77-20871, TOP LEFT EGT SIGNAL T495S4 WAS OUT OF RANGE REMOVED AND REPLACED THE TOP LEFT EGT T49.5 PROBE IAW AMM 77-21-01-000-400. ACCOMPLISHED POWER ASSURANCE CHECK IAW AMM 71-00-00-700-813-F00, ENGINE PARAMETERS WERE WITHIN LIMITS. DURING ENG RUN PARAMATERS 18C N1 88.5 EGT 567 OPS CHECKED NORMAL.