Toyota 90916-03100
Thermostat

Service and repairs of the thermostat start with drained engine coolant followed by V-bank cover uninstallation. Release the No.2 hose clamp or clip on the radiator outlet before erasing the water inlet and thermostat and gasket by removing the 3 nuts. Begin by checking the magnitude of water valve opening temperature on the thermostat before dipping it into water and heating the water slowly as you confirm the valve opening temperature falls between 80 to 84 degrees Celsius (176 to 183 degrees Fahrenheit). Replacement of the thermostat must be done when the valve opening temperature does not match the specified range of 80 to 84 degrees Celsius (176 to 183 degrees Fahrenheit). The valve lift needs inspection while the water reaches 95 degrees Celsius (203 degrees Fahrenheit) because any measurement under 8.0mm (0.31 in.) requires a thermostat replacement. A fully sealed valve must exist prior to a thermostat reading below 40 degrees Celsius (104 degrees Fahrenheit). Replacement of the thermostat becomes necessary if the valve remains open. New gasket installation begins with placing it on the water inlet that includes the thermostat then tightening the 3 nuts to 9.0 Nm (92 kgf/cm, 80 in. lbs.). First reconnect the radiator outlet using the No.2 hose clamp or clip while adding engine coolant before checking for leaks. Use the provided 2 nuts to reinstall the V-bank cover and torques them to 7.5 Nm (76 kgf/cm, 66 in. lbs.).

The service process of a thermostat requires all engine coolant to be drained before proceeding. Begin the water inlet service by detaching it from the water inlet housing through removing the 3 nuts. Start by discarding the thermostat followed by removal of its gasket. To inspect the thermostat you should heat water while submerging the component to verify its valve opening temperature is within the range of 80 - 84 degrees Celsius (176 - 183 degrees Fahrenheit). The thermostat needs replacement if these criteria are not met. A thermostat replacement is necessary if the valve lift is less than 10 mm (0.39 inch) while operating at 95 degrees Celsius (203 degrees Fahrenheit). You should replace the thermostat when it fails to completely close below 40 degrees Celsius (104 degrees Fahrenheit). Insert the new gasket onto the thermostat before placing it into the water inlet housing with the jiggle valve oriented straight upward toward 30 degrees of either side of the designated position. Screw and tighten the three water inlet nuts to 19 Nm (195 kgf-cm, 14 ft. lbs.). Check the engine oil level and top it up if necessary. Subsequently start the engine and validate coolant leaks before rechecking the coolant amount.

Engine servicing of the thermostat begins with draining the engine coolant first. The water inlet must be detached from the housing after removing the 3 nuts which secure it. The servicing process begins with removing the thermostat and its installed gasket. Check the valve opening temperature of the thermostat while heating it with water by immersing it in a container. Replace this part if it shows a temperature reading below 80 degrees Celsius to 84 degrees Celsius (176 degrees Fahrenheit to 183 degrees Fahrenheit). The replacement of the thermostat is necessary when the valve lift measurement is less than 10 mm (0.39 inch) at 95 degrees Celsius (203 degrees Fahrenheit). The valve needs to achieve complete closure when the temperature reaches or falls below 40 degrees Celsius (104 degrees Fahrenheit). If this condition cannot be achieved then get rid of the thermostat. The water inlet housing installation process requires the thermostat to receive a new gasket then the valve should go into position while facing vertically upwards within 30-degree tolerance from the recommended slot. Secure the 3 water inlet nuts with correct torque value of 19 Nm (195 kgf-cm, 14 ft. lbs.). Engine coolant filling must be followed by engine start-up then a leak test before confirming the correct engine coolant measurement.

The service procedure for repairing a thermostat starts by emptying the engine coolant. The removal of three nuts allows you to disconnect the water inlet from the water inlet housing. First step involves removing the thermostat together with its gasket from the system. The valve opening temperature of the thermostat must be checked between 80 - 84 degrees Celsius (176 - 183 degrees Fahrenheit) when the device is heated in water; a replacement thermostat is necessary if the specifications are not met during inspection. The valve lift measurement must exceed 10 mm (0.39 inches) at 95 degrees Celsius (203 degrees Fahrenheit along with complete valve closure below 40 degrees Celsius (104 degrees Fahrenheit). Replace the thermostat if the specified properties do not match. When installing the new gasket on the thermostat you should place it into the water inlet housing with the jiggle valve oriented straight upward in a position that can fall between 30 degrees of either side of the specified direction. Affix the water inlet to its place using 3 nuts before tightening them to 19 Nm torque value (195 kgf-cm or 14 ft. lbs.). Check the engine coolant first then add coolant to the system followed by examining for leaks and validating the coolant level.

Immerse the thermostat in water and gradually heat it, checking that the valve opening temperature is between 80 to 84°C (176 to 183°F).

Reinstall the water inlet using the 3 nuts, torquing to 19 Nm (195 kgf-cm, 14 ft. lbs.).

Immerse the thermostat in water and gradually heat it, checking that the valve opening temperature is between 80 - 84°C (176 - 183°F).

Install the water inlet using the 3 nuts, torquing them to 19 Nm (195 kgf cm, 14 ft. lbs.).

First, drain the engine coolant.

Place a new gasket on the thermostat and insert it into the water inlet housing with the jiggle valve facing straight upward, which may be set within 30° of either side of the prescribed position.

Place a new gasket on the thermostat, install the thermostat with the jiggle valve downward, and secure the water inlet with 3 bolts, torquing them to 20 Nm (200 kgf-cm, 14 ft. lbs.).

Connect the lower radiator hose, fill with engine coolant, start the engine, and check for coolant leaks.

Disconnect the radiator outlet by removing the No.2 hose clamp or clip.

Fill the system with engine coolant, start the engine, and check for coolant leaks, then recheck the engine coolant level.

First, drain the engine coolant.

Reinstall the water inlet using the 3 nuts, torquing them to 19 Nm (195 kgf-cm, 14 ft. lbs.).