So I thought I had it fixed but I was wrong. It started up just fine after replacing the fuel filter but I think it was just a fluke. The engine was still warm from running it before. The old filter didn't appear to be dirty so I don't think that really did anything. I've had some time to work on it the last couple days. I replaced the fuel lines from the tank to the filter and from the filter to the injection pump just to rule out any potential clog, collapsing line, or air leak. I have really good fuel flow through the filter to the injection pump. So I'm about 95 percent sure the problem is either in the injection pump or the injectors or the lines between them. When I crank the engine I get NO smoke at all out of the exhaust so I believe that tells me no fuel is getting through the injectors. So I pulled the injectors out thinking maybe they were clogged (don't know if that is a common problem as I've never worked on a diesel engine before). I took each injector apart and cleaned it. They didn't appear to be worn out or dirty really at all and I was surprised how simple they are each one consists of about 6 parts. There was just a little carbon build up on the tips of the injectors. Put them back together and back in. Made no difference. About a minute or two of cranking cold (still no smoke at all from exhaust until it starts) and it starts just barely and has very little power. Before I attached the metal lines from the injection pump to the injectors I cranked it to check how much fuel was spurting out of the lines. Each line squirts a small amount of diesel in sequence. I tried this at full throttle and minimum throttle thinking there might be more squirting out at full throttle and appears to be no difference. So I'm thinking maybe there is not enough pressure to push them through the injectors? When I get it running the throttle control works as it should Is there some way I could check the pressure? I'm worried I may have a bad injection pump ($1200). Or maybe the injectors are bad? I tried using starting fluid and just a tiny squirt at the air filter housing will start the tractor immediately both times I tried it cold. I never let the tractor warm up during all this just tried to keep it cold. When I let the tractor warm up for about 15 minutes (seems like a long time to get it warmed up) it seems to have almost adequate power and I could even run it in high gear without it bogging down too much but only when it was FULLY warmed up. Last thing I checked was while I had it running at minimum throttle I tried loosening each of the three fuel lines one at a time. I did this to see if it was running on all three cylinders. Each time I loosened a line it started running like crap so I know it is running on all three cylinders. When it is running at medium or high throttle or minimum throttle fully warm it purrs nicely and the engine sounds good, but just not adequate power. I probably should have tried before but I'm going to drain all the fuel and make sure it has good diesel. Now that I think of it that really might be the problem and I feel like a dummy now for not doing that before. Also I checked out the glow plugs and one of them was bad. I ohmed them and one was bad but to be sure I pulled out all three, completed the circuit to ground and checked to see if they get red hot and two of the three did But I don't think the glow plugs really have anything to do with my fuel problem. So....after my long story.......any thoughts? I'm gonna go change out the fuel now.