4. The noise comes from the needle mechanism.

Product reasons: Needle bar, needle bar sleeve, small connecting rod and other wear and tear are too large. The small connecting rod screw rod crank screw is loose.

Treatment: Replace the new parts and tighten them.

5. The noise comes from the feeding mechanism.

Product reason: the large spigot conical screw is worn or loose, the feeding tooth touches the needle plate, and the needle spacing adjustment mechanism is loose.

Treatment: Grind or re-adjust, re-adjust, re-adjust or tighten the screws.

6. The noise comes from the shuttle mechanism.

Product reason: the shuttle and the shuttle bed wear cause the gap to be large, and the gap between the shuttle and the shuttle is too large, causing an impact.

Treatment: Replace new parts, adjust or replace new ones.

7, general noise.

Product reason: The upper shaft, the lower shaft and the sleeve are worn, causing the upper and lower sides to move, and the machine is short of oil.

Treatment method: replace the new parts, or adjust the gap between the upper and lower shaft planes, pay attention to maintenance, and refuel on time.