Neighbor borrowed my 24T and, long story short, his hired man pulled the knotter apart. They got it back together but, when I went over to see why it wouldn't tie, I found that the tucker fingers were beginning their cycle too soon; tips of TF actually scraping by the needle tips as the come up. They apparently had both the needle cam and the knotter clutch off and my sense is that one, or both must be one spline off on the main knotter shaft causing the intermittent gear to engage the pinions too soon. These knotters are fairly simple and designed to be easy to repair so I would assume that there are some sort of "timing" or "register" marks and/or a procedure to get the needles and the knotting mechanism back in sync. In looking at the mechanism (pic below) I see an inverted "U" shape on the intermittent gear and a corresponding nub on the frame bracket. Could aligning these be the answer? If not, what might it be?