This comprehensive Husqvarna Huskylock S21 S25 Service and Adjustment Manual provides detailed instructions for maintaining and repairing your sewing machine. The manual covers a wide range of topics, including:

* **Basic adjustments:** Learn how to adjust the presser bar height, needle bar height and parallelism, needle timing, lower looper height, clearance between the looper and needles, upper looper positioning and timing, chain stitch looper height and clearance, and more.
* **Feed system adjustments:** Explore the feed timing, feed dog height, differential feed (for the Huskylock S21 model), and lower and upper knife adjustments.
* **Thread path and tension:** Understand how to set the lower and upper looper thread guides, adjust the chain stitch looper thread take up and guide, and fine-tune thread tension for both the Huskylock S21 and S25 models.
* **Service program for the Huskylock S25:** This section provides specific instructions for servicing the S25 model, covering troubleshooting and repair procedures.
* **Circuit board diagrams:** The manual includes diagrams for the Main PC Board and Power PC Board, facilitating understanding of the machine's electrical components.
* **Troubleshooting chart:** This helpful chart assists you in diagnosing and addressing display and screen issues.