Thanks for all the good tips and advice and thanks California for helping me confirm it's age, I figured it was a '77 as well, the rear wheels aren't stock, they look maybe to be Kabota. As for the ''clank, clank'' noise, once I learned it wasn't a problem, and is just how these 2 bangers sound, I kinda like the noise, i'm kinda proud of it. I've really enjoyed going through all the posts here, reading about how ya'll found your Yanmars, in many cases resurrected them from becoming scrap, and It's been a real eye opener to see how many implements and the workload your tractors handle. It's also great to see how so many of you offer advice and help troubleshooting when someone has a problem with their machine. I've spent hours surfing this site and I've learned a lot about the proper way to use and maintain my machine, like I said, I would not of bought this tractor had I not found this site. It's also good to see that there are companies like Hoye that have a dependable supply of replacement parts. There is something cool about using a 30 yrs+ old machine that still runs the way it was designed to run, it's the same reason I drive a 1975 ford f100 pick up, they both have great, simplistic design that withstands the test of time and are easy to work on and they're also a small piece of history from when things were built better and meant to last! peace.