Bell 206L, Maintenance Manual

Page: 185 / 220

BHT-206L4-MM-1
5-00-00
7 JUN 2013 Rev. 18 Page 149 Export Classification C, ECCN EAR99
CAUTION
IF MAIN ROTOR MAST HAS EVIDENCE OF
TORSIONAL YIELDING, THE MAST ASSEMBLY,
TRANSMISSION ASSEMBLY, MAIN DRIVESHAFT,
AND FREEWHEEL ASSEMBLY (OUTER RACE,
I N N E R R A C E , A N D C L U T C H ) S H A L L B E
C O N S I D E R E D U N S E R V I C E A B L E A N D
SCRAPPED. MAJOR DAMAGE TO THE MAST
ASSEMBLY OTHER THAN TORSIONAL YIELDING
REQUIRES REPLACEMENT OF TRANSMISSION
TOP CASE. IF TRANSMISSION TOP CASE HAS
TO BE SCRAPPED, PYLON MOUNT SPINDLES
A N D M A S T B E A R I N G S S H A L L A L S O B E
SCRAPPED.
(b) Torsional yielding may be detected by
measuring the offset between the mast splines above and
below the main rotor trunnion split cone groove using either of
the following methods:
i. Sliding a 0.1600 inch (4.06 mm)
diameter measuring pin across the upper and lower spline.
ii. Sliding a straight edge across the upper
and lower unworn face of the spline (coast side of the spline).
BHT-206L-CR&O c. Transmission assembly.
d. Swashplate assembly.
NOTE
Replace all control bolts from hydraulic servo
actuators to main rotor hub.
e. All cyclic and collective control tubes from mixing lever
to swashplate.
f. Main rotor pitch link assemblies.
g. Freewheel assembly.
CONDITIONAL INSPECTIONS
5-51. SUDDEN STOPPAGE/ACCELERATION — MAIN ROTOR (CONT)
DATA REFERENCE INSPECTION TASK DESCRIPTION
INITIAL
MECH OTHER