Hi all. I am running into a new issue with my 1999 New Holland TC 18 tractor. I've been having fuel issues. I had some gunk from the tank clog up the incoming fuel line. So, I drained tank and tried to get rid of as much debris as possible then rehooked up the lines and bled the lines and everything seemed to be back on track. However, I was out mowing last week and ran into the same issue. Another clog. So, I had to tow my tractor back to garage and do everything over again. After bleeding the fuel line for air I went back out to try and finish prior mow however, I noticed immediately that the tractor would not accelerate. It drives but it's almost like it's driving in Low rather than High. Curiously enough, when I go to back up it will back up as normal with the "fast speed". It's only impacting the forward motion and not reverse. I am totally clueless. One thing I may mention is that when doing all the repairs, the throttle line popped off the little pulley box it attaches to so I had to replace it. Other than that I am totally clueless. Anyone got any tips as to what to look for? I'm a noob and trying my best at this DIY stuff.