Water pump blew up in Death Valley on the eastbound climb up Towne Pass, having not gotten far from Panamint Springs on the 3500′ ascent. The water pump shaft bearings gave out and caused coolant to leak past the shaft, and got sprayed all over under the hood by the engine fan draft. Before the truck overheated, was able to turn it around on a section of state route 190 along the climb. Coasted back down the hill to Panamint Springs, where I caught a ride from one of the proprietors to the nearest town of Lone Pine. Luckily the pump failed when and where it did, because within just 50 miles prior, I was venturing alone along the south pass trail from Saline Valley.
Once in Lone Pine, was able to purchase a new $138 water pump unit (p/n 45000) from the Napa Auto Parts store, along with specialty tools like a pulley holder (p/n 3900) and 47mm wrench (p/n 3473) required to change the pump. Also purchased 5 gallons of pre-mixed engine coolant formulated for diesel engines. At over 279,000 miles when the water pump failed, in retrospect, should have also purchased a new thermostat. New fan clutch was not in stock at the auto parts store at the time.
List of parts to consider replacing, while the 7.3L’s water pump is removed: fan clutch, serpentine belt, idler pulley, upper radiator hose, lower radiator hose (contains internal support spring), thermostat, coolant
When completing the water pump replacement and reattaching the fan clutch, it helps to use a strap or belt to suspend the heavy fan and fan clutch assembly in order to start the 47mm nut. It’s a tight squeeze between the radiator, fan shroud, and front of the engine, that one slip and fumble of the fan could easily poke a hole in the radiator.