Replaced upper and lower loopers on a 1988 Singer serger machine. Fussed around with the timing of the thing for a good 2-3 hours and couldn't get it to work right. Still skipped stitches. Replaced the cheap Chinesium loopers with expensive factory Singer parts and in 15 minutes got it working perfectly. No more skipped stitches. Should be good to go for another 30 years now.
