working on Farmall MD that has been sitting 10+ years. Runs great on gas side, but dies when switching to diesel. Rack wouldn't move so took injector pump off, took out plunger, cleaned up, made sure plunger seemed to be free, got rack moving fine, reassembled and put back on tractor. When bleeding air at injectors, have steady stream of diesel at number 3 and tractor still dies, any recommendations, do I need to take distributor block off of injector pump and make sure valves free to move? Also, have diesel at all injector bleeds even when fuel lever off. Fuel pressure gauge reads full pressure.