Q: How do you remove the thermostat for Chevrolet Blazer,S10,GMC Jimmy and Sonoma?
A: To remove the thermostat, start by draining about 1 gallon of coolant from the Radiator until the level is below the thermostat housing. Then, remove the air intake duct and disconnect the radiator hose from the thermostat cover. Next, remove the bolts and lift off the cover, tapping it with a soft-face hammer if necessary to break the gasket seal. Take note of how the thermostat is installed, and then remove it. Make sure to use a replacement thermostat with the correct opening temperature. If a gasket was used, use a scraper or putty knife to remove any old gasket material and sealant from the mating surfaces. To install the new thermostat, ensure the correct end faces out, with the spring directed toward the engine. Use a new rubber gasket or apply a bead of RTV to the groove in the coolant outlet sealing surface if no gasket was used. Carefully position the cover and tighten the bolts to the specified torque, being careful not to over-tighten and risk cracking or distorting the cover. Reattach the radiator hose and tighten the clamp, and consider checking and replacing hoses and clamps at this time. Finally, refill the system, run the engine, and carefully check for any leaks.