Open the face plate and look inside. Here you will find the tension release spring which is attached to the tension release lever (the lever that lifts the presser foot); the tension release pin and the set screw.
I have a plastic ice cube tray that I use to keep the individual pieces organized. I can put a little denatured alcohol in each little cube so that the parts can soak while I am dis-assembling.
First I turned the chrome knob all the way, as loose as it would go. Then I pushed on the numbered dial to release the little stud in the chrome knob and removed the knob
Once the chrome knob is removed, you can see the numbered dial simply sits on the tension stud.
The tension discs and check spring all come out together.
Once your parts are clean, it is a matter of putting things back in the order they came out.
First the tension stud with the pin placed inside properly (head oriented in the stud as it is the photo above). If you, like me, prefer your -/+ spring housing to sit horizontally, you need to make sure that the tension stud is oriented as indicated in the photo.
The numbered dial goes next. Somewhere I read that the number 2 goes on top of the tail on the stop washer. I have no idea why, or if it makes a difference. I do try to do it, though.
A very wise Bill Holman of Vintagesingers (http://groups.yahoo.com/group/vintagesingers) suggested that I re-word my instructions. So I have cut and pasted his suggestion here. He is the smartest man on the planet when it comes to these machines. I am honored that he read my blog and took the time to make this suggestion.
I would suggest something more like: Once the tension is adjusted so that it is
correct on your test fabric, push in on the numbered dial while holding the knob
in position, rotate the dial to 3 or 4, and let it pop back out against the