I was in possession of one of those machines and when it stopped working right I took it to be professionally repaired/serviced. I've been taking machines in to this guy for more than a decade and he's really good. He sighed and said "I hate working on those!" and up to then I had been sure he hadn't met a vintage machine he didn't like! Machine was returned in good working order to the person who loaned it to me and I was glad to say goodbye to it.