Common repairs for Singer sewing machines include cleaning the machine, polishing the needle plate and adjusting the top tension. The exact steps to repair a Singer sewing machine depend on the specific problem.
A sewing machine that does not change tension when the tension dial is turned usually needs to be cleaned to remove lint. Lint or thread caught between the tension discs is a common cause for tension change problems. It is important to ensure that the top thread is between the disks after re-threading the machine.
Damage around the needle hole of a Singer sewing machine can cause the top thread to keep breaking. Fixing the problem involves using a needle file or fine sand paper to polish any burrs on the needle plate. A damaged hook is another cause of this problem. Extra care should be taken when sanding the hook to avoid changing the shape of the hook tip.
Needles that break often are usually caused by the top tension being too tight. This problem is fixed by simply adjusting the tension to a medium number. Using the incorrect needle size or type for the thickness of the fabric often causes needles to break. Types of needles include regular point, wedge point and ball point.