Thank you for your question.
I can see your concern for knowing how this reverse lever works it you cannot sew in reverse.
• I am sorry but the manufacture only shows a parts breakdown for this machine.
• When you push on the reverse button you should feel some resistance from the internal mechanism and it should push back when you release it. If you do not, the lever on the inside is either broken or stuck.
• Because of the complexity of how sewing machines are built, I would recommend taking the machine to a sewing machine repair person.
• If you want to look at some of the reverse mechanism you can remove the bottom covers both for the base and the free area and locate the link lever that works the reverse.
• Then remove the top cover for more light so you can see better.
• I am going to give you a picture with the red highlighted to make sure this link is connected.
If you do not feel confident repairing this problem yourself, then you can have it repaired by a Sears technician. Here is a link that will provide the nearest drop-off locations:
Sears Home Services
I am sorry that I could not be of more help.
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