Janome 2149SX Service Manual page 5

CONDITION
6. NOISY 1. BACKLASH BETWEEN
OPERATION SHUTTLE HOOK GEAR AND ADJUSTMENT "CLEARANCE
LOWER SHAFT GEAR IS TOO BETWEEN NEEDLE AND HOOK
GREAT.
2. LOWER SHAFT GEAR IS
LOOSE.
3. INAPPROPRIATE BELT
TENSION.
4. UPPER SHAFT GEAR IS LOOSE. ELIMINATE THE LOOSENESS.
5. NOT ENOUGH OIL.
7. DEFORMATION 1. INAPPROPRIATE ZIGZAG
PATTERN SYNCHRONIZATION.
2. INAPPROPRIATE
DISENGAGEMENT OF CAM
FOLLOWER.
3. UPPER THREAD TENSION
IS TOO STRONG.
4. INAPPROPRIATE FEED
BALANCE.
CAUSE
3
HOW TO FIX
SEE MECHANICAL
(NO.2)".
ELIMINATE THE LOOSENESS.
SEE MECHANICAL
ADJUSTMENT "MOTOR BELT
TENSION".
OIL ALL MOVING PARTS.
SEE MECHANICAL
ADJUSTMENT "NEEDLE
SWING".
SEE MECHANICAL
ADJUSTMENT
"DISENGAGEMENT OF CAM
FOLLOWER".
ADJUST UPPER THREAD
TENSION CORRECTLY.
SEE MECHANICAL
ADJUSTMENT "DISTORTED
PATTERN ".
REFERENCE
P.13
P.23
P.10
P.22
P.7
P.17