Service difficulty report · Thermocouple · Boeing 737724

Difficulty date
July 7, 2026
Submitted
July 9, 2026
Operation
Air carrier
Aircraft
N23708
Make and model
Boeing 737724
Aircraft serial
28769
Aircraft time
85,305 hours, 31,582 cycles
Engine
Cfmint CFM567B242
Part
Thermocouple
Part number
TC29603
Part serial
4483
Condition
Faulted
Location
Nr 1 Engine
Part time
1 hours, 1 cycles
Stage of operation
CL
How discovered
O
Nature of condition
J
Precautionary procedure
A

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

What was found

ENGINE 1 EGT IN AMBER RANGE DURING CLIMBOUT AT THRUST REDUCTION & ACCELERATION ALTITUDE 1112 FT. DURING TAXI OUT FLUCTUATING ABOUT 20 SPORADICALLY AT LOW POWER SETTINGS. IAW FIM 77-21 TASK 803, BITE TEST FOUND MAINT FAULT 77-20861 FOR BOTTOM LT EGT SIGNAL (T495S3) IS OUT OF RANGE. S3 BOTTOM LT PROBE PREVIOUSLY REPLACED. GIVEN PREVIOUS HISTORY & EGC ON L/P 9520053, R & R CJ10 HARNESS. IAW AMM 73-21-06. ENGINE EXPERIENCING AN INTERMITTENT EGT INDICATION ISSUE. R & R ENGINE 1 CJ10 HARNESS. IAW AMM 73-21-06. VERIFIED INSTALL OF NR 1 ENG EEC J10 WIRE HARNESS IAW 73-21-06-400-802-F00. STILL FADEC SYSTEM TEST, TASK 73-21-00-700-802-F00. R & R J10 HARNESS IAW AMM 73-21-06-400-802-F00, R & R THERMOCOUPLE IAW AMM