Service difficulty report · Probe · Boeing 737890

Difficulty date
October 25, 2016
Submitted
October 31, 2016
Operation
Air carrier
Aircraft
N557AS
Make and model
Boeing 737890
Aircraft serial
35176
Aircraft time
39,750 hours, 11,731 cycles
Engine
Cfmint CFM567B27
Part
Probe
Part number
TC29604
Condition
Failed
Location
Nr 2 Egt
Stage of operation
IN
How discovered
9
Nature of condition
O
Precautionary procedure
K

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

What was found

FOUND ECONOMIC FAULT FOR NR 2 ENGINE 77-20862. THE BOTTOM LEFT EGT SIGNAL (T495S3) IS OUT OF RANGE. ACFT GROUNDED. PERFORMED INPUT MONITORING OF T49.5 CONTROL TEMPS. FOUND S3 TEMP WAS DASHES. CONTINUED TO TROUBLESHOT IAW FIM REF 77-21 TASK 803. INSPECTED AND CLEANED S3 CONNECTOR AND EGT PROBE IAW AMM 77-21-01-200-801-F00. AFTER CLEANING RECONNECTED S3 AND RECHECKED T49.5 CONTROL TEMPS. S3 DISPLAYED NORMAL TEMPERATURE. RESISTANCE CHECK SHOWED EGT PROBE (S3) OUT OF LIMITS, CJ 10 HARNESS CHECKED GOOD BUT APPEARS SUSPECT. REMOVED AND REPLACED S3 T49.5 PROBE IAW AMM 77-21-01-000-801/F00 AND 77-21-01-400-801-F00. REMOVED & REPLACED CJ10 HARNESS, IAW WDM 77-21-11. PERFORMED EEC CHECK IAW AMM TASK 73-21-00-700-804-F00 AND AMM TASK 71-00-00-700-807-F00, ALL TEST PASS, NO FAULTS.