Crusty free poly 318 and where it came from.

Every thing looks to have been in place, the bearings were scored a bit, and the front main bearing looked to be starting to rotate. The connecting rods are in one piece. The owner of the backhoe bought this from a guy because it is just like the one his father used to use in their family buisiness-dirtwork, tiling, tree removal, etc. in the past. Said to have sat in the same spot for at least 20 years before he got it. I am guessing water got into it while sitting, not sure if there was a carb on it over that time.