Replaced the water pump a few weeks ago DIY in the driveway. Hardest part was getting the fan clutch nut loose from the water pump's threaded pulley shaft.
I got an 1-7/16" open end wrench from Tractor Supply for $15. I did not need to grind it down flatter as others have mentioned. Then I fabricated a pulley holder out of some 1/8" x 2" wide steel flat bar by drilling two holes in the end and cutting out a section with a jig saw. Tractor supply or Home Depot carry lengths of this bar stock. The hole center spacing is 45mm. Make sure the cut out is wide enough & goes slightly past the holes so the fan clutch nut clears the bar so you can get the (2) pulley bolts thru it.
Basically you loosen the 4 pulley bolts while the serpentine belt is still on. Leave them finger tight though. Remove two of the bolts and install the modified steel flat bar using those same bolts back in the pulley. My 2001 main fan clutch bolt had RH threads. I used a 2"x4" laying across the top of the engine bay to hold the steel bar steady as I tapped on the 1-7/16" wrench with a short heavy maul (hammer) It came loose with a few taps.
I tried using a big strap wrench and other methods but none worked until I did this bar and wrench method. I replaced the serpentine belt Bando #6PK2200 while I was in there
I got an 1-7/16" open end wrench from Tractor Supply for $15. I did not need to grind it down flatter as others have mentioned. Then I fabricated a pulley holder out of some 1/8" x 2" wide steel flat bar by drilling two holes in the end and cutting out a section with a jig saw. Tractor supply or Home Depot carry lengths of this bar stock. The hole center spacing is 45mm. Make sure the cut out is wide enough & goes slightly past the holes so the fan clutch nut clears the bar so you can get the (2) pulley bolts thru it.
Basically you loosen the 4 pulley bolts while the serpentine belt is still on. Leave them finger tight though. Remove two of the bolts and install the modified steel flat bar using those same bolts back in the pulley. My 2001 main fan clutch bolt had RH threads. I used a 2"x4" laying across the top of the engine bay to hold the steel bar steady as I tapped on the 1-7/16" wrench with a short heavy maul (hammer) It came loose with a few taps.
I tried using a big strap wrench and other methods but none worked until I did this bar and wrench method. I replaced the serpentine belt Bando #6PK2200 while I was in there