OEM 2001 Toyota 4Runner Thermostat

2001 Toyota 4Runner Parts Questions & Experts Answers

• Q: How to service and repair a thermostat on 2001 Toyota 4Runner?

  A: The first step for servicing or repairing the thermostat includes draining engine coolant then disconnecting the lower radiator hose. You need to remove the thermostat by disassembling the water pump where you detach its three nuts and wire clamp and water inlet and thermostat along with its gasket. After that remove the gasket from the thermostat. Adults should test the thermostat function by submerging it in water and conducting a temperature test to verify the valve opens between 80 - 84 degrees Celsius (176 - 183 degrees Fahrenheit) and achieves a lift of 8.5 mm (0.335 inch) at 95 degrees Celsius (203 degrees Fahrenheit). Thermostat replacement is needed if the specifications fail to meet the requirements. Complete valve closure is required at temperatures below 40 degrees Celsius (104 degrees Fahrenheit). Failure to achieve proper valve closure indicates the need to replace the thermostat. Installation of the thermostat requires a new gasket and placement of the jiggle valve in the downward position before screwing three bolts which should be torqued to 20 Nm (200 kgf-cm, 14 ft. lbs.). Connection of lower radiator hose follows by engine coolant filling and engine start-up permits leak detection.