Removing the Thermostat

• 1). Open the hood and disconnect the ground (black) battery cable with a wrench.
  
  
• 2). Place a drain pan under the radiator and open the radiator drain valve. Drain about 2 qt. of coolant and close the drain valve.
  
  
• 3). Remove the air filter box and any ducts from the assembly on the 2.3L model, so that you gain better access to the thermostat housing. Use a ratchet, ratchet extension and socket.
  
  
• 4). Follow the upper radiator hose to where it meets the engine. On the 2.5L engine model, the radiator hose is connected to a water pipe, which connects to the thermostat housing. On the 2.3L model, the hose connects to the thermostat housing.
  
  
• 5). Unscrew and remove the bolt that secures the water pipe to the engine on the 2.5L model, using a ratchet, ratchet extension and socket. Carefully pull the water pipe off the thermostat housing and remove the O-ring located between the pipe and housing.
  
  
• 6). Unfasten the bracket holding the engine harness to the engine using a wrench, and move the harness to the side on the 2.5L model. This is also the upper mounting bolt for the thermostat housing.
  
  
• 7). Unfasten the lower thermostat housing mounting bolt on the 2.5L model. On the 2.3L model, unfasten both housing mounting bolts. Use a wrench to remove the bolts and lift the thermostat housing, thermostat and gasket off the engine. Note the mounting position of the thermostat so that you install the new one in the same position.
  
  

Installing the New Thermostat

• 1). Wipe out any grime off the housing and engine mating surfaces with a brush and shop rag.
  
  
• 2). Position the new thermostat on the housing with the jiggle pin pointing upward on the 2.5L model, then place the new thermostat gasket with the projection on the gasket in the same direction as the jiggle pin. On the 2.3L model, position the new thermostat, along with a new gasket, on the thermostat housing aligning the projection on the thermostat with the notch in the housing.
  
  
• 3). Install the thermostat housing on the engine and the lower mounting bolt finger tight on the 2.5L model. Replace the bracket for the engine harness and the mounting bolt finger tight. On the 2.3L model, install both bolts finger tight as well. Tighten bolt bolts on both models with the wrench.
  
  
• 4). Mix about 1 qt. of new antifreeze and 1 qt. of distilled water in a clean container. Dip a new O-ring for the water pipe in the coolant mix for the 2.5L model.
  
  
• 5). Connect the water pipe to the thermostat housing along with the new O-ring and secure the pipe to the engine with the mounting bolt using the ratchet, ratchet extension and socket on the 2.5L model.
  
  
• 6). Add the new coolant mix to the radiator and connect the ground (black) battery cable with the wrench.
  
  
• 7). Replace the air filter box and any ducts from the assembly you had to remove on the 2.3L model, using the ratchet, ratchet extension and socket.
  
  
• 8). Start the engine and wait for about 20 minutes for the new thermostat to open. When this happens, you will see the coolant flowing through the radiator neck. Turn off the engine and replace the radiator cap.
  
  
• 9). Add more coolant to the reservoir, which connects to the radiator neck with a rubber hose, to bring the level up to the "Full" mark, if necessary, and close the hood.