The needle bar of the old sewing machine is crooked, how can I adjust it?

1. Open the mask, loosen the fixing screw on the needle bar connecting rod, add some oil to the needle bar, move up and down several times, tighten the screws on the needle bar connecting rod, and then add a little oil to all moving parts.
2. The shuttle bed is installed incorrectly, or there is a thread and cloth in the shuttle bed, the shuttle is stuck on the shuttle bed, and the shuttle holder cannot swing the shuttle, causing the entire mechanism to fail to operate.
3. Reinstall the shuttle bed correctly, swing the shuttle, and clean the thread and cloth inside the shuttle bed to solve the problem.