How to Replace the Water Pump on a 1998 Chevy Malibu
- 1). Drain the coolant from the cooling system by placing a drain pan under the radiator on the driver's side and unscrewing the drain valve located at the bottom of the radiator. Remove the pressure cap from the coolant recovery tank located on the passenger's side inner fender well.
- 2). Remove the black plastic belt guide, located above the water pump housing on the front left side of the engine. Use an 8-mm socket and ratchet to remove the bolt that attaches the guide to the pump housing. The serpentine belt routing guide for the Malibu is shown on the decal on the top of the belt routing guide.
- 3). Loosen the four 10-mm pulley bolts using a 10-mm wrench. Remove the serpentine belt by rotating the tension arm--located on the passenger side of the engine to the left of the water pump--counterclockwise to release the tension on the belt. Slip the belt off the water pump pulley when the tension on the belt is released. Remove the pulley bolts, and lay the pulley and bolts aside.
- 4). Remove the five 8-mm water pump bolts that attach the pump to the pump housing using an 8-mm socket and ratchet. Pry the pump off the front of the engine using a large screwdriver.
- 5). Clean the gasket sealing surface on the front of the water pump housing using a gasket scraper to remove all traces of the old gasket. Install the new pump gasket, supplied with the new pump, on the pump using gasket adhesive to stick the new gasket into place on the pump.
- 6). Install the pump into the water pump housing and tighten the 8-mm bolts in a star-shaped pattern to ensure even tightening of the bolts. Reinstall the water pump pulley, the serpentine belt, and the belt guide.
- 7). Fill the cooling system with coolant by pouring a 50/50 mix of water and antifreeze into the coolant recovery tank. Open the air bleed screws on the top of the thermostat housing and the tube attached to the back of the water pump housing. Continue to add coolant with the bleeder screws open to allow trapped air to escape from the system. Close the bleeder screws, and start the engine. Open the bleeder screws, one at a time, to allow any remaining air to escape, and close them when only coolant escapes.
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