For those machines that do not ZZ removed the face plate and get the Tri-Flow in behind the light and sheet metal part to the mechanism. As I said above that area is not normally oiled. The owners manual that I have does not give any instructions to oil, or where to oil. But the ZZ parts under the nose need it.
My machine would take quite a bit of sewing before the ZZ and patterns would work. It was gummed up from the old oil under the nose. Tri-Flow and soaking fixed it right up.
Joe