i am replacing my waterpump on my 99 blazer 4.3, i cant seam to get the fan off my haynes manual says to keep the waterpump pully in place and remove the large nut, but my question is how do i keep the pully from moving, do i need a special tool

 

There is a special tool set that can remove the fan. I was able to do it with my large adjustable wrench and a pry bar. I positioned the prybar between the large hex and one of the puley mounting nuts. I spun it around until I found a spot where the pry bar didn't fight the initial loosening of the large nut (ie, not sitting on a flat). Once it is broke loose even a tiny bit, it should be easy to turn off from there.

 

could you explain what you mean by hex

 

thank you i figuerd out what you ment and it worked thanks man

 

Congrats! Glad I could help!!