Genuine Hyundai Santa Fe Thermostat

Hyundai Santa Fe Thermostat Parts Questions & Answers

• Thermostat Assembly
  25500-35531
  Q: How to replace a thermostat in a cooling system?

  A: Before assuming the thermostat is responsible for a cooling system problem, check the coolant level, drive belt tension, and temperature gauge (or light) operation. If the engine takes a long time to warm up, the thermostat is probably stuck open. Replace the thermostat with a new one. If the engine runs hot, use your hand to check the temperature of the lower Radiator hose. If the hose is not hot, but the engine is, the thermostat is probably stuck in the closed position, preventing the coolant inside the engine from escaping to the radiator. Replace the thermostat. Caution: Do not drive the vehicle without a thermostat. The computer may stay in open loop and emissions and fuel economy will suffer. If the lower radiator hose is hot, it means that the coolant is flowing and the thermostat is open. A more thorough test of the thermostat can only be made when it is removed from the vehicle. If the thermostat remains in the open position at room temperature, it is faulty and must be replaced. To test it fully, suspend the (closed) thermostat on a length of string or wire in a container of cold water, with a thermometer. Heat the water on a stove while observing the temperature and the thermostat. Neither should contact the sides of the container. Note the temperature when the thermostat begins to open and when it is fully open. Compare the temperatures to the Specifications. The number stamped into the thermostat is generally the fully-open temperature. If the thermostat doesn't open and close as specified or sticks in any position, replace it. To replace the thermostat, drain the cooling system. Follow the radiator hose to the thermostat housing cover and disconnect the hose. Remove the thermostat housing cover mounting fasteners and remove it from the cylinder block. Be prepared for some coolant to spill as the gasket seal is broken. Remove the thermostat, noting the direction in which it was installed in the housing, and thoroughly clean the sealing surfaces. Fit a new gasket onto the thermostat. Make sure it is evenly fitted all the way around. Install the thermostat and housing, positioning the jiggle pin at the highest point. Tighten the housing cover fasteners and reinstall the remaining components in the reverse order of removal. Refill the cooling system. Run the engine and check for leaks and proper operation.