I replaced my upper and lower thermostats on my truck and it stopped the leak but now it's overheating. I put the not gasket end into the block for the lower and the not gasket end inside the housing. I think that maybe the upper thermostat might be backwards. Not sure tho. How do I know for sure
My car has 69000 miles.
My car has an automatic transmission.
Installing a thermostat upside down will cause the engine to overheat. Although not impossible, the thermostat will fit better one direction than the other. The coiled or spring loaded end needs to go into the engine block. The end with the "seal" goes into the thermostat housing.
Think about the thermostat opening up when more coolant is needed, and put the moving end in the engine block. If you are sure the thermostat is installed properly, and that the unit you put in has not failed ("new" parts do come faulty sometimes), then you should look to your water pump next. The symptoms from these two components' failure are very similar.
To avoid any unnecessary repairs, consider YourMechanic, as one of our mobile technicians can come to your location to diagnose the overheating issue and fix it accordingly. Best of luck.
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