Coolant leak?

Most likely it is the water pump. They are not real hard to change. Start the cooling system draining. While that is happening, loosen the pulley bolts, then remove the belt. That way you do not have to fight the bolts as much. With the belt out of the way you can remove the pulley and remove the pump. Clean off any sealer and apply the new sealer. Bolt the new pump in and reverse the removal process. While you have the belt loose inspect it and the tension-er.

This guide can help us find it

https://www.2carpros.com/articles/car-is-leaking-coolant

Next would be the thermostat housing, it is right above the center of the engine. The gasket can fail and they will leak down the face of the engine. I have also seen the ears on the bottom fail where the bolt holds them on and leak because of that. The biggest issue with them is you have to remove the exhaust crossover to get to the housing. If the car is rusted that can be difficult. To make that easier you can get a couple candles, run the engine so the exhaust is warm and then rub the candles on the bolt threads on the crossover flanges so it can wick into the threads. It will work as a lubricant and help in removal.

Pressure testing is not hard, you can usually get the tool as a loaner tool from a parts store. Then let the engine cool off. Fill it full of coolant and pump it up to 15 psi. and look for the leak. Many will leak long before getting up to pressure.

No problem. Thanks for being someone who actually wants to repair it and does not dump five cans of super duper leak sealer in, then wonder why the radiator and heater no longer work.
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