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2.5L, 2.8L and 4.3L Gasoline Engines
See Figures 10, 11, 12 and 13
Disconnect the negative battery cable, then drain the engine cooling system.
Relieve the belt tension, then remove the accessory drive belts or the serpentine drive belt, as applicable.
Remove the upper fan shroud, then remove the fan or fan and clutch assembly, as applicable.
Remove the water pump pulley.
Loosen the clamp and disconnect the coolant hose(s) from the water pump.
On some engines, such as the heater hose on the early 2.8L, removal may be easier if the hose is left attached until the pump is free from the block. Once the pump is removed from the engine, the pump may be pulled (giving a better grip and greater leverage) from the tight hose connection.
Fig. 10: Water pump mounting - 2.5L engine
Remove the retainers, then remove the water pump from the engine. Note the positions of all retainers as some engines will utilize different length fasteners and/or bolts and studs in different locations.
Using a putty knife, carefully clean the gasket mounting surfaces.
The water pumps on some of the earlier engines covered by this repair guide (early 2.8L's and 2.5L's for example) may have been installed using sealer only, no gasket, at the factory. If a gasket is supplied with the replacement part, it should be used. Otherwise, a 1/8 in. (3mm) bead of RTV sealer should be used around the sealing surface of the pump.
Apply(NNN) NNN-NNNNor an equivalent sealant to the threads of the water pump retainers. Install the water pump to the engine using a new gasket, then thread the retainers in order to hold it in position.
Tighten the water pump retainers to specification:
For the 2.5L engine tighten the water pump-to-engine retainers to 17 ft. lbs. (23 Nm).
For the 2.8L engine, tighten the retainers to 22 ft. lbs. (30 Nm).
For the 4.3L engine, tighten the bolts and studs to 30 ft. lbs. (41 Nm). Fig. 11: Applying sealant to a water pump on an early model 2.8L engine Fig. 12: Water pump mounting - 2.8L engine Fig. 13: Water pump mounting - 4.3L engine (note that stud locations may vary)
Fig. 11: Applying sealant to a water pump on an early model 2.8L engine
Fig. 12: Water pump mounting - 2.8L engine
Fig. 13: Water pump mounting - 4.3L engine (note that stud locations may vary)
Connect the coolant hose(s) and secure using the retaining clamp(s).
Install the water pump pulley, then install the fan or fan and clutch assembly.
If equipped with a serpentine drive belt, position the belt over the pulleys, then carefully allow the tensioner back into contact with the belt.
If equipped with V-belts, install the accessory drive belts and adjust the tension.
Install the upper fan shroud, then connect the negative battery cable.
Properly refill the engine cooling system, then run the engine and check for leaks.