How to Replace the Water Pump in a Mercury Grand Marquis

The Mercury Grand Marquis is a dependable car with exceptional performance and looks to match. Rarely is major repair required for this car; however, routine maintenance can go a long way toward keeping your Marquis on the road for a very long time. One part of routine maintenance that your Grand Marquis may at some point require is replacing the water pump in the cooling system. The water pump circulates the coolant in the system throughout the engine to keep the internal temperature cool.

Things You'll Need

  • Socket wrenches
  • Coolant
  • New Pump
  • Put the car in park and crawl underneath the driver's side of the radiator. Locate the radiator drain plug and use the socket wrenches to remove it. Allow the coolant to drain out into the catch container and discard.

  • Crawl under the passenger side of the engine compartment and locate the water pump housing on the bottom of the engine. It is a silver, conical housing with four mounting bolts. Loosen the hose clamp holding the hose on the pump with the screwdriver. Use the socket wrench to remove the four mounting bolts, and then slide the housing and the water pump underneath off of the engine.

  • Slide the new water pump in place and tighten down the mounting bolts. Slide the hose in place on the new pump and tighten down the hose clamp bolts. Uncap the radiator and pour a 50/50 solution of coolant and water in the radiator until it is full. Turn the car on and allow it to warm up to normal operating temperature. Continue filling the radiator with coolant until the reservoir is full.