A bad water pump on the BMW 318I cannot properly circulate the engine coolant throughout your engine. When this happens, the engine will begin to overheat. If you do not repair it in a timely manner, more expensive repairs could result. The project is not difficult and you can easily do it yourself. It will take about an hour and a half to complete, and you can find the required tools in most home toolboxes.
Make sure the engine is cool before starting this project. Open the valve on the bottom of the radiator and drain the coolant into the drain pan. Place the drain pan out of reach of children and household pets. Disconnect the hoses from the radiator using the screwdriver to loosen the hose clamps.
Remove the retaining bolts from the radiator and pull it from the BMW. Remove the fan blade from the engine by loosening the retaining bolts with a wrench. Remove the water pump pulley using a wrench to remove the bolts. Remove the engine lift hook using a socket and ratchet.
Remove the mounting bolts from the water pump using the socket and ratchet. Pull the pump away from the engine along with the old gasket. Remove any remaining gasket material from the engine block with the scraper. Place a new gasket and water pump on the engine block and secure the bolts with the socket and ratchet.
Install the engine lift hook and secure the bolt with a socket and ratchet. Install the water pump pulley and tighten the bolts with a wrench. Install the fan blade and tighten the bolts with a wrench. Install the radiator and tighten the bolts. Connect the radiator hoses and tighten the clamps with the screwdriver.
Make sure the valve on the radiator is closed. Refill the radiator with engine coolant and start the BMW to check for leaks.