I bought a Grasshopper 1210 ZTR off of Craigslist and it worked fine for the first couple of uses. However, the blade belt bound up and had to be replaced, now the replacement seems to be wearing unduly fast. I tried adjusting the tension, but it still seems to get very hot within 10 minutes of running. Also, the hydros seem to be operating erratically. Sometimes the left side can't keep up with the right and then the opposite. I checked with the local dealer on what to put in the hydros and they told me for the old style that is used in this model to just use straight 30W motor oil. I'm using this to mow trails which are not the smoothest. As I said earlier, it really worked well for the first couple of times. When I go out, it's usually for a couple of hours at a time. Although today it didn't even last 1 hour before I started to notice a smell that made me check the blade belt (again) and that's when I noticed that a fine black powder was being created. I stopped mowing and drove it back. I adjusted the belt tensioner about 1/2" and when I went back out, the motor started to bog while cutting. I've done a search on the web for this model and can't find anything useful. It was only made in 1985 & 6. I've never had a ZTR before and don't want to do more harm trying to resolve these issues. Any suggestions would be greatly appreciated.