I recently bought Progress - a 1936 wooden tug. She has a wonderful Fowler 2DYm engine, which deserves to be in the percussion section of an orchestra, never mind a boat! I'm trying to stock up on spares and am searching for a replacement drive belt. The current one has this inscription: 3002 592x91 12,5X1275LA 42-3388 DAYCO. Sadly, I am not familiar with how to decode this in order to buy another one. According to the very helpful chap in Midland Chandlers (Braunston), I'm after one that is 12.5mm wide and 1275mm in circumference. Trouble is, I can't fine one online anywhere. I can find something seemingly close - such as 13X1275 - but the letters are different (specifically, it reads '13AX1275C'). I am very new to engines and mechanics in general and have no idea whether the tiny extra width (13mm rather than 12.5mm) would make any difference (can't imagine it would) nor whether the letters mean something important. In other words, is 13AX1275C essentially a perfectly good replacement for a '12,5X1275LA'...?
Any help would be hugely appreciated.
Thanks in advance.