I know I have been asking a lot of questions. I replaced my thermostat. Before I
did this the car overheated, so that's what I thought it was. Flush and filled the
coolant system. The car is overheating more since I did the thermostat. Could
the thermostat be junk?
Was the cooling system purged from the air pockets after refilling the cooling system? Another possibility is a bad water pump. And if this is a North Star engine chances are there is a bad head gasket. You can get a kit for check the coolant for exhaust gasses indicating a bad head gasket.
I purged the system, checked the head gaskets, they were all fine. Is there a possibility that the radiator is plugged. I believe the water pump is fine.
What's a good way to check the water pump?
Well it is hard to just tell on the water pump without removing it. The impeller that circulates the coolant deteriorates. I guess one could have the radiator coolant level down a inch or two, and see how it is circulating threw the radiator. You should be able to see the circulation, but like you mention, if the radiator is plugged up, you wouldn't see it circulate.
I don't see it circulating, the only thing it does when the car gets up to temp is the water starts coming out of the resevoir tank.
I don't see it circulating, the only thing it does when the car gets up to temp is the water starts coming out of the resevoir tank. What this a sign of?
Either the cooling system needs to be purged from the air pockets or a bad head gasket, or when this is happening the engine is starting to overheat due to the water pump. I would first try purging the cooling system if you have not done so, and if that didn't take care of it, before getting into a water pump, have the coolant tested for exhaust gasses, indicating a bad head gasket.
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