If the manual shows a Singer 15 with the stitch length lever you are pretty safe. -88 is the subnumber for threadle, 91 for potted motor. I think 89 is for belt driven motor, other wise exactly the same. The are a lot of variations on the 15, some have slighly different threading, tensioner, bobbin winder and bobbin case, but I think all the ones with stitch lenght lever and reverse are the same. You don't need to think about grease on the treadle version, just find a good oil and detect all the oil points. Maby you can use grease on the treadle irons, but use oil if you don't take it appart.
Last edited by Mickey2; 06-26-2018 at 07:54 AM.