I have a white 43 rotary machine. It was given to me and I just finished oiling and cleaning it up. I am baffled by the fact that after threading it and putting in the bobbin, that the normal procedure to pull up the bobbin thread does nothing. I have to press the knee lever for just a few stitches and then it will loop the bobbin thread and I can then pull it up. I have tried manually turning the wheel with the pressure foot up and with it down. It will not grab the bobbin thread. It is only when I run the machine will it grab it. Can anyone tell me what would cause this? It is kind of a pain because sometimes the motor runs a bit too much and then I get a tangle instead. Ahhhhh