ok i changed the thermostat today and refilled the antifreeze and burbed it and let it idle for about 30 mins and the fan cut on and was working...i tok it for a 10 mile drive and temps stayed good i came back to shop and when i went to go home after driving about 5 miles the temp started to creep up about a 1/4 inch from hott so i flip the heat on and it when right back to normal and never moved from there..i noticed that my resovoir is a 1/2 from being full again...seems like when it pushes water in there it dosent suck it back in..im stumped i replaced the thermo switch thats in the head i havent replaced the one thats in the thremo neck..im lost...