NH bc5070 short pigtails

Our five year old NH 5070 square baler has very short pigtails on the knots. Any suggestions on how to make them longer? It rarely misses a knot, but the tails have gotten to where they are only 1/4" long. It hasn't seemed to cause any problems yet, but I'm concerned about the knots pulling apart if they get any shorter. We switched from sisal to 170 plastic this year. Tails are short either way. Plastic does work better, but still have very short tails. I tried tightening both the twine disc spring, and the billhook spring slightly like the manual said. Made no difference. The dealer said to loosen the twine disc spring from where it was originally. That made no difference either. I also loosened the twine holder plate coming out of the twine box to the point where there is just enough tension to keep the twine from falling out. The tucker fingers are 1/8" to left of needle slot in the home position with slight pressure on them. The short tails haven't seemed to cause any problems yet, but I'd like to lengthen them out before problem arise. Anyone have any experience on this?

NH bc5070 short pigtails