HELP..Can't get cooling fan off pump

I am in the middle of trying to replace my water pump on a 1996 GMC Sonoma. I have the pump and cooling fan disconencted but I can't seem to get the cooling fan off the pump in order to replace the pump. Does anyone out there have any ideas as to how I can do it?? Getting pretty frustrated with this thing!

Thanks in advance.

There is a special tool to remove the fan clutch from the pump.

You could try a large wrench on the nut and smack the wrench with a hammer.

The wrench and hammer method that GMMerlin mentioned works fine. Here is a copy of the procedure that I posted in the Jimmy forum:

1)Drain the coolant:

2)Remove the shroud:
7-10 mm bolts

3)Remove the fan and clutch:
There is no need to separate the fan from the clutch. The whole thing threads on to the end of the water pump. I don't know the size, because rather than break out all my wrenches, I just grabbed an 18 inch crescent wrench. Place the wrench on the nut and tap loose with a hammer. the tapping will break it loose. You have to tap it, if you just try to loosen it, the belt won't hold it and the whole thing will turn. After it breaks loose just spin it off.

4)Break loose the bolts holding the pulley on:
4- 13 mm or 1/2" bolts
Just break them loose, don't remove them

5) Remove the serpentine belt

6) Remove the pulley:
Finish removing the bolts holding the pulley and remove the pulley

7) Disconnect the hoses

8) Remove the old pump:
4-14 mm or 9/16" bolts

9) Clean the surface:
Remove all traces of the old gasket.

10) Install new pump:
Apply a bead of blue Permatex around the holes on both sides of the gaskets, put them on the pump and insert the bolts through the holes to hold the gaskets in place. Carefully lower the pump in to position. Thread the bolts into the block and snug them. Then remove the bolts one at a time, add the permatex to the threads, and then reinsert. (only do one at a time so that the pump doesn't shift and disturb the mating surfaces) Then tighten all the bolts.

11) Reinstall everything in reverse.

There will be a lot of air trapped in the system, so after you fill it, get the engine to operating temperature, shut it off, let it cool, then add more. The air trapped in the system can cause your engine to over heat if left unattended.
I suggest filling the system with water only and run it like that for a day or two just to make sure there are no leaks. That way you don't waste your antifreeze if you have to do further repairs.

Thanks for your help! I got it off....great instructions. Now I just have to wait for Canadian Tire to get the new parts in tomorrow.

Thanks again.