Thanks guys! I had no idea that could even be done. I have a lot to learn about cranks and treadles and would love to learn how to do conversions. I am going to make a note you mentioned it and add it to the file I have on that machine. I am not happy with how he has this one set-up anyway. Apparently the motor was bad so he used a blue Morse motor on it and the belt isn't lined up well so that was going to have to change anyway.
I think it's weird that I ended up taking on so many machines because I would consider myself a newbie to fixing up old machines. I only started doing this last year and still have a LOT to learn. Each sewing machine I work on teaches me something new so it looks like I will be learning a lot! I don't even own a hand crank and would love to convert one to crank sometime too. That will be on my to-do list once I whittle the pile down a bit.
Of these two Kenmores one is very lightweight, the light green one is a super heavy machine! I ended up with 5 15's in all but this one is a centennial. There are 3 27's. This little lady is the oldest one I have. Her serial number dates back to 1896.