I am restoring my 4T proofing press from the early 1950s and am dealing with replacing the motor belt. I bought a new one from NA Graphics (thanks, Fritz) because the old one was pretty badly dry-rotted even though it still functioned. Even with much adjustment to the height/position/angle of the motor in putting the new belt on, something about the tension/angle isn’t right because my belt keeps flying off the pulleys – literally! Fritz recommended taping the edge of the pulley to create a lip. It worked for a while, then it popped off again. If anyone has any experience specifically with doing this task on a 4-T, I welcome any/all advice. Maybe I just haven’t found the positioning sweet spot yet, but I’m losing valuable press time to this task. Thanks in advance for sharing your experience!