Textron Bell 412, Maintenance Manual

Page: 104 / 288

BHT-412-MM-2
5-00-00
Page 68
Rev. 26 01 JUN 2018 Export Classification C, ECCN EAR99
a. Hanger assemblies — bearings and surrounding areas
for evidence of grease leakage, condition, damage, security,
corrosion, and overheating. Discoloration of bearing (color
change to blue or blue/black) or multi-color appearance of
hanger that darkens adjacent to bearing is evidence of
overheating. Brown color of bearing shield is normal and is not
evidence of overheating.
b. Driveshaft sections for cracks, rivet failure, distortion,
dents, corrosion, and damage to anodized finish.
c. Clamp sets for condition, security, and proper
installation.
WARNING
CAUSE OF ANY DISCOLORATION SHALL BE
DETERMINED AND CORRECTED PRIOR TO
NEXT FLIGHT.
d. Flexible couplings and surrounding areas for grease
leakage, damage, corrosion, and evidence of overheat as
indicated by TEMP-PLATES or coupling discoloration. A
change in color of one or more of the red bordered
TEMP-PLATE dots from white/off-white to black indicates an
overheat condition and may require replacement of both outer
and inner couplings (step e).
e. Overheat TEMP-PLATES for condition and security.
TEMP-PLATES must not show evidence of over temperature
indication, deterioration, debonding, or excessive discoloration
of the epoxy overcoating.
NOTE
Step 8 pertains to helicopters S/N 36020 through
36999, S/N 37002 through 37999, S/N 38001
through 38999, S/N 39101 through 39999, and
helicopters modified by 412-570-001-103 or Post
BHT-412-SI-74 (412SP to 412HP Upgrade).
SCHEDULED INSPECTIONS
5-9. 25 HOUR/30 DAY INSPECTION — PART B (CONT)
DATA REFERENCE INSPECTION TASK DESCRIPTION
INITIAL
MECH OTHER