How to Fix a Water Pump in a 1988 Chevy Pickup
- 1). Drain the cooling system. Place a pan under the driver's side of the radiator and twist the drain valve wing-nut clockwise until coolant drains into the pan. Remove the radiator cap from the top right of the radiator by twisting it counterclockwise as you push down on it. When the coolant stops draining close the valve.
- 2). Remove the four 3/8-inch bolts that attach the upper fan shroud to the lower fan shroud, using a socket, extension and ratchet. Remove the four 3/8-inch bolts that attach the upper fan shroud to the radiator core support. Lift the shroud out of the engine compartment.
- 3). Remove the four nuts that attach the fan blade to the front of the water pump pulley using a 7/16-inch wrench. Pull the fan forward, off the water pump studs, and lift it out of the engine compartment.
- 4). Loosen the upper alternator bolt using a 1/2-inch wrench and slide the alternator toward the center of the engine. Loosen the A/C compressor bolts using a 9/16-inch wrench and push the compressor toward the center of the engine. Remove the belts and the water pump pulley.
- 5). Loosen the lower radiator hose clamp using a screwdriver. Pull the hose off the water pump. Loosen the heater hose clamp, which attaches the heater hose to the top of the water pump, using a screwdriver. Remove the four 9/16-inch water pump bolts using a socket, ratchet, and extension. Pull the pump from the front of the engine and out of the heater hose..
- 6). Stick the new gaskets, supplied with the new pump, to the pump using gasket adhesive. Clean the gasket surface on the engine using a gasket scraper to remove all traces of the old gasket. Coat the inside of the heater hose and the lower radiator hose with a thin film of silicon grease.
- 7). Slip the water pump into the heater hose and bolt the pump to the front of the engine. Tighten the heater hose clamp. Slip the lower radiator hose onto the pump and tighten the clamp. Reinstall the pulley, belts, fan and upper fan shroud.
- 8). Fill the radiator with a 50/50 mix of anti-freeze and water and start the engine. Let the engine run until it reaches operating temperature and the coolant level drops in the radiator. Top off the coolant in the radiator and fill the coolant recovery bottle to the "Full" level marked on the side of the bottle. Reinstall the radiator cap and check for leaks.
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