Overheating problems

[HDwatki at aol.com]

    Here in the Mid-Atlantic states , it's starting to get hot.  And of 
course I'm have them problems in my 4kq.  It hadn't completelely overheated 
until today but it has been running a little warmer durning these warm days.  
At night it's fine I guess because it's cooler.  Today it boiled over.  When 
I got out of work I saw a little coolant under the car and notice that that 
sensor ( what is that sensor that sticks out from the front of the block at 
the bottom) was wet.  I have also been able to smell a faint odor of 
antifreeze inside the car.  After getting home to take a closer look and I 
did notice that the leads from the fan need to be clean but it had been still 
coming on.  Any ideas.  Thanks

Duane 85 4kq