Service difficulty report · Shutoff Valve · Bombdr DHC8402

Difficulty date
March 28, 2021
Submitted
March 30, 2021
Operation
Air carrier
Aircraft
N450QX
Make and model
Bombdr DHC8402
Aircraft serial
4452
Aircraft time
15,157 hours, 16,472 cycles
Part
Shutoff Valve
Part number
8209713
Part serial
200203266
Condition
Inoperative
Location
Engine Bleed Sys
Part time
35,801 hours, 37,386 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

#1 AND #2 BLEED HOT CAUTION ILLUMINATED DURING ROTATION. DURING BLEEDS OFF TAKEOFF. RUNNING THE CHECKLIST CAUSED CAUTIONS TO EXTINGUISH. DIVERTED. REMOVED FROM SERVICE. FOUND FAULTS 7008,7004,3801 AND 3102 IN FAULT HISTORY FOR LEFT CHANNEL AND 7008,7004,3801,3102, AND 1006(RNAPRSOV) FOR RIGHT CHANNEL. DURING HIGH POWER RUNS DUPLICATED BOTH BLEED HOT CAUTION LIGHTS ON WITH BLEEDS SELECTED OFF. AND PRESENT FAULTS 3102,7008,7004,1601 IN BOTH CHANNELS. REPLACED RNAPRSOV REF AMM 36-11-19-000-801/400-801 FOR CODE 1006. WHILE PERFORMING OPERATIONAL TEST OF BLEED AIR SYSTEM REF AMM 36-11-00-710-802, BOTH #1 AND #2 HPSOV VALVES FAILED OPS TEST. REPLACED BOTH HPSOV VALVES REF AMM 36-11-09-000-801/400-801. OPS CHECKS GOOD. COULD NOT DUPLICATE DISCREPANCY AGAIN AT HIGH POWER SETTINGS. AIRCRAFT RETURNED TO SERVICE.