Service difficulty report · Motor · Saab SF340A

Difficulty date
April 12, 2001
Submitted
May 8, 2001
Operation
General aviation
Make and model
Saab SF340A
Part
Motor
Part number
M3348A
Condition
Unapproved Part
Location
Fan
Component
Fan · Dynair
Component part number
C209690C
Stage of operation
IN
How discovered
C
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

FAN RETURNED TO DAE FOR UPGRADE TO C209-690D CONFIGURATION. THE FAN WAS TESTED AND FOUND TO EXHIBIT EXCESSIVE VIBRATION. WHEN THE FAN WAS DISASSEMBLED, IT WAS DISCOVERED THAT THIS OVERHAULED UNIT HAS NOT BEEN OVERHAULED PER THE DAE OVERHAUL MANUAL. THE ARMATURE AND STATOR FIELD WINDING ARE NOT OF DAE DESIGN. DAE OVERHAUL MANUAL DOES NOT ALLOW FOR THE REWINDING OF THE ARMATURE OR FIELD WINDINGS. THE ARMATURE ASSY HAS AN OVERSIZE COMMUTATOR INSTALLED WHICH MAKES THE BRUSHES EXTEND PAST THE DESIGNED LIMIT, THE IMPELLER IS AT THE WRONG LOCATION, AND ARMATURE IS NOT BALANCED. THE FIELD WINDINGS ARE REWOUND AND HAVE UNACCEPTABLE AIR GAP.

More about the Saab SF340A