Trying to fiqure out this engine code on my rollback motor (hope I attached the image link correctly) - As per the picture the number is C51118820 and the digits to the right that are not fully in the picture are K11 18 TXB which I think mean it was built in Ontario on November 18th with the TXB meaning it is a 1975 350 from a C-20 to 3500. I was asked if it was a four bolt main which I do not know and was hoping this would clear it up along with any other info it may provide. Thanks in advance, Jay
