I think it was a couple years ago the singerco.com went bye, bye. It was a good resource.
I believe some of the the manuals listed on ismac.net are no longer valid, either. For some manuals a good resource is manualslib.com and I think that sometimes they have service manuals or sometimes called adjuster's manuals. There is service manual for 319 on ebay.
The vintage Singer sewing yahoo group moved to io groups over a year ago.
Janey - Neat people never make the exciting discoveries I do.
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