Okay, i finally got to really use my b7100 wedesday to cut about 2 acres of grass with a finishing mower and i noticed that after about 30min of use the radiator overflow line had a little steam coming out so i stopped cutting let it cool down and checked the coolant level and it looked fine the radiator fins weren't stopped up so i don't know what else it could be i will try flushing it out before i use it next time. thanks