I looking at a bobcat to buy. The owner says its a 631 but it has a Wisconsin engine so it must be a 630. It makes a noise when it steers right. There is a video on you tube. I have not seen the machine yet I’ am looking for some insight on what the noise could be. I’ am guessing something with the chain or a wheel bearing. He said one of the rear wheels locks up sometimes. Here is a link to the video if it works. If not if you type in bobcat 631 on you tube it comes up. Also what is this machine worth in this condition? Thanks http://www.youtube.com/watch?v=zq_YSKWB62Q