I'll resurrect this old thread just to provide the resolution since I just now remembered I never did! So I had been using Normde2001's advice and had been shutting of the fuel every time I got finished using it (only 3-4x a year) and then changing oil/filter when it got thin but last winter I finally got it fixed. The pump was more than I wanted to tackle myself but luckily a new pump/injector shop opened up in town last year so they were kind enough to do the whole job. I will say they were not used to Yammer Hammer, they first thought something was broken inside but when I said they all sound that way they started diagnosing. They first thought it was the pump as well but took it off and tested it and it was fine so they checked both injectors, initially he thought both of them were fine as well but pressure started bleeding off an injector and he noticed a crack in a copper shim or busted o-ring or something so he rebuilt both injectors. I can tell you this thing had only been running on one cylinder for a long time! I hooked it up to the tiller after I got it home and what used to drag the tractor down and almost kill it, will now go through w/ no effort whatsoever. So just a word of caution to maybe check your injectors before replacing or rebuilding the injector pump.
