The 1998 Jeep 5.2-liter V-8 motor is a modern variant of the classic 318 Chrysler motor used primarily in the Grand Cherokee, which uses a water pump to circulate coolant through the cooling system. This pump, located at the front of the engine, can wear out or be damaged and require replacement. Replacement can take the average backyard mechanic about an hour.
Instructions
- 1
Disconnect the lower radiator hose by turning the hose clamp counterclockwise (or pinching the clamp with a pair of pliers) and working the hose from the radiator nipple. This will open the coolant system--and it will begin to drain, so have the drain pan handy. Allow the radiator to drain, which might take several minutes. The lower radiator hose attaches to the water pump at its other end, and removing the hose entirely will save time later and give better access to the pump. Loosen the hose clamp and work the hose off like before, and you can drop the hose through the bottom of the Jeep.
2Remove the electric engine cooling fan and fan shroud, using a wrench to turn the four bolts on each corner of the shroud counterclockwise. Disconnect the fan by unplugging the wiring harness adapter plug from the socket on the fan case. Pull the entire unit out as one piece, up and out of the engine compartment.
3Remove the serpentine drive belt from the water pump pulley wheel by pressing on the tension pulley arm firmly and sliding the belt out from underneath the idle pulley. Release the arm, and the belt will have enough slack to come free of the water pump.
4Remove the three hoses attached to the pump by turning the hose clamp screws with a screwdriver, loosening the hose clamps and working the hoses free by hand. In many cases, these hoses are aged and can be difficult to work off. By sliding a screwdriver between the hose and the pump nipple, you can work around the nipple and eventually free the hose. There is limited space when working in this area, so use a short screwdriver or dull knife. Coolant will spill out when the hoses come off, so have the drain pan handy.
5Remove the pump by turning the pump's four main mount bolts with a wrench. The pump pulls directly out, toward the front of the Jeep. Replace the pump, and scrape off any old gasket from the motor with a screwdriver. The new water pump should come with a new gasket, oriented to the openings in the pump. Replacement is the reversal of the removal. Once you've sealed the cooling system, add the proper amount of coolant through the radiator filler neck and check the level often over the next few weeks.
