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V Range 501
l
651
l
801 Maintenance Manual
MA8:4
Chapter - Fault Diagnosis
Fault
Symptom Possible
Cause
No pickup performance
1.
Hopper full, causing airflow to be throttled: - Discharge load.
2.
Nozzle or nozzle trunking blocked or restricted by debris.
Check the nozzle water jets are not blocked, are working
correctly and lubricating the intake duct.
3.
Intake flap not open (dual m/c’s). Blanking plate not removed
after using the Wanderhose (single m/c).
Poor pickup performance
1.
Nozzle not set to the optimum opening., i.e. too close to
ground.
2.
Nozzle trunking partially restricted by debris. Check nozzle
water jets are working correctly and so lubricating the duct.
3.
Channel brush incorrectly set, not directing debris in line
with nozzle.
4.
Intake flap not fully opened (dual m/c’s).
5.
Rear body meshes blocked or restricted.
6.
Low oil level in fluid flywheel.
7.
Air silencer pack in roof of cowl blocked with debris and/
or sound absorbent material separating from its substrate
causing a restriction.
8.
Fan case inlet make and break seal fitted to inlet of fan case
either degraded and not sealing or missing.
Note:
The fan case outlet seal, unlike the inlet seal, has no
effect on air performance and only provides the function of
a dust seal.
9.
Engine is not running at correct operational speeds. Check
fuel filter or air filter blocked/ causing a restriction.
Page Issue A
SUCTION SYSTEMS
