I read this thread and I am hoping I can get some help. My mother in law just gave me her Singer 615U which she received as a graduation present. It was NEVER used. The motor/timing belt disintegrated and I need to replace it. I have not been able to find any dimensions on it such as length or width or number of teeth on the belt. Since this machine was a OCONUS item information is difficult to locate. I have the original manual and all the other original items it came with but no repair or parts information. If anyone has any information I would be grateful if you could share it.