I have a John Deere 316 that just doesn't seem to be running right. The problem is this. It takes a little bit to start. When it does start, it runs good, in low throttle. As soon as you kick it up, it takes a little bit to catch up, but then seems to run good. A little rough, but good. As soon as you start to drive, it bogs down and dies. It doesn't do it if you are moving at a snails pace, but if you you are driving anywhere over 3 mph, it will die. As soon as you engage the PTO, it really goes nuts and you can't move at all or it will die. I rebuilt the carburetor, checked the fuel pump (diaghragm type) and checked spark. The left side seems to have a weak spark, but still gets spark. I tried looking up a compression guide for the "B" series engine and it says there should be a minimum 100 p.s.i per cylinder. I'm getting a reading of about 90 p.s.i. . Would that make this thing run that bad? If anyone has any ideas, please help!!!! I'm racked here:00000060: Thank You!!