Any sewing machine oil should work on your featherweight and I have never touched my motor or taken the case off. If your featherweight is stitching well and not growling, it should be fine. A visual check of your cords should show you if they should be replaced ($8) at my local dealers. If they're not cracked and feel pliable and not stiff or hard, they should be fine. Any good quality needles (schmetz) and thread (Gutterman works on mine) will be fine. I haven't found the featherweight to be picky about any thread or needles. Just make sure that the flat side is inserted correcly and you don't get any little bits of thread stuck in the bobbin case. Check your manuel for the correct threading. Featherweights will sew demim or a couple of layers without skipping or jumping. Your machine may have come with a guide as to seam width or you can purchase one. Plates with seam widths marked are also available. This little machine is tougher than it looks.