Agree with all above. Mine stays at 82 consistently.
I did a multi flush, water pump, Tstat, hoses, belts job a couple months ago. Don't use any goop on the Tstat gasket - the PO had gobs of that crap at the Tstat gasket and the water pump gasket. The Tstat gasket is rubber and seals nicely. Make sure you put it back in the proper direction and rotation - there are posts about it. Soak your bolts, they are small and fragile. I used the same ones over on the Tstat but replaced all the bolts for the water pump - they had seen much better days
