Hello, I own a 1999 863 with the 73 hp duetz motor. Cleaning up around property and noticed when ever I put a load on machine. The machine would lose power and motor would start fluttering. Remove the load and it would go back to running smooth. So I started by changing fuel filter. After I changed the filter. I started machine up and let it run for bit to make sure there were no issues. After bout 5 min I noticed fuel dripping from what seemed like all the braided return lines. I bought and installed a new return line kit earlier this year. So all the lines are in great shape. So I know those are fine. It seems like there is a back pressure causing the fuel to leak out of the return lines. Any ideas what is causing this? Maybe a bad injector? If it is an injector issue. Is that what could have been causing the loss of power issue? I didn't look to see if fuel was leaking before I replaced the fuel filter. I'm just hoping I don't have to break into the fuel system of this machine as I hear it can be some what of a nightmare. If it is an injector. Is it as simple as replacing injector bleeding fuel line and being done? Or is there more to it than that? I'd appreciate any advice or input. Thanks