I have begun replacing my thermostat, but I have a bolt unable to be removed from the thermostat housing.
It is common for this to occur on this engine. It is typically due to corrosion caused by electrolysis. Once this occurs the bolt almost fuses itself to the metal around it. In some cases, using a penetrating lubricant can get into the threads and loosen it. From my experience with this engine, I typically need to break the bolt and re-tread the hole and use new bolts. If you are going to have this done, consider YourMechanic, as a certified mechanic can come to your home or office to repair this.
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