I'm trying to remove the stitch length shaft on a 112w139, seem someone dropped it on the hand wheel. The main top shaft appears to be bent. I have removed the hand wheel and can pull the shaft out about 1.5", then it stops. I have not touch anything inside of the head. I get it out enough to see the shaft appears to be split and that is where it stops dead. Must be something I am missing. Also are there any manuals that show exploded view for singer machines. Thanks Andy