LEMON Manuals: Even more car manuals for everyone
Home >> Buick >> 2004 >> Century Limited >> Repair and Diagnosis >> Engine Mechanical >> Cooling System (Mechanical) >> Engine Cooling System >> Diagnostic Information and Procedures >> Thermostat Diagnosis (Overheating)

Thermostat Diagnosis (Overheating)

Thermostat Diagnosis (Overheating)

Step Action Yes No
IMPORTANT: The J 24731  Tempil Stick is a pencil-like device that has a wax material containing certain chemicals which melt at a given temperature. See Special Tools and Equipment . Use the temperature sticks to determine a thermostats operating temperature by rubbing 87° C (188° F) and 97° C (206° F) sticks on the coolant outlet. The marks made by the sticks should melt when coolant temperatures reach 87° C (188° F) and 97° C (206° F), respectively. These temperatures are the normal operating range of the thermostat.
1
  1. Remove the radiator cap. Refer to Draining and Filling Cooling System .
  2. Rub a 97° C (206° F) J 24731  on the coolant outlet. See Special Tools and Equipment .
  3. Warm up the engine at fast idle.
  4. Check for coolant flow before the mark begins to melt.
Is there coolant flow before the mark melts?		 Go to Step 2  Go to Step 3 
2 The problem is caused from something other than the thermostat. Refer to Engine Overheating .
Does the engine still overheat?		 - System OK
3
  1. Replace the thermostat. Refer to Thermostat Replacement (3.1L)  or Thermostat Replacement (3.8L) .
  2. Check the system
Is the engine still overheating?		 - System OK
scientia non olet · About LEMON Manuals