Why does antifreeze leak and it only smell when the car is running and sitting still?

Answer 1

First, the smell is prevalent due to the lack of motion. When your auto is moving down the road, the smell travels after the fact. Mass in motion creates an envelope, known as an air pocket in front of and around your vehical. Thus, all of your oddors from your ride is displaced behind your ride. You can smell other peoples rides on the road when you approach them from allong side or from behind them. However, once you stop moving, your oddors catch up with your ride. Since you are not moving away from the smell. When your car is moving down the road, your engines' water pump is turning faster then at the idle sitting position. Thus, the fluids are moving at a much higher pressure rate as the RPMs pick up.The water pump is driven by the belt system on your engine, being either a surpentine or individual belt. As the motor speeds up, so does your water pump. As your motors RPMs pick up, the pump moves fluide faster, generating higher pressure values and the symple dynamics of fluide in motion. Your thermostat valve will open automatically allowing the fluide to move through the engine and out through the radiator. This is how your cooling system functions. Engine warms the fluide, at a set temp. the thermostat opens to allow the fluide to escape from the engine block. The water pump circulates the fluide through the engine and out to the radiator. The radiator is designed to allow the fluide to pass through its core of coils that are exposed to the air flowing through its openings in the design of the core. This fluide has had the heat drawn out of the fluide mixture. This is the same principle as an air-conditioning system and heat pump are set up in your homes.And swamp coolers are similar in this design as well. So ow you have it, air cools the fluide before it is pumped back into the motor to help maintain the recommended opperating temperature of the engine. Which is between 190 to 220 deg F. I do hope this was broken down enough for all to gather a better understanding of their engine cooling system and why you only smell it when you come to a stop. As for the leaking, once you stop, your pump is not moving the fluide as fast as it is when under a load. So the pressure that was built up in the entire cooling system under a much higher load factor needs a place to go. That is why we have the over-flow canisters. It helps to save your coolant mixture and balance out the fluide load. Tis pressure is created from the fluide in motion. Due to the cavitation caused by the pump and imbalance of fluides in the system. Air bubbles are introduced into the fluide as the pump circulates the coolant at a much higher rate. This is also seen on the prop of a boat when the transum is raised partially out of the water and the prop is exposed above the water line. Thus you have the churning of the surface water and the open air being drawn into the water. This is cavitation.Now your engines cooling system has introduced air into the system from between the radiator and the thermostat. The water pump circulates the fluide in the engine until the thermostat opens and then the cooler fluide is allowed into the engine abd the pump moves the hot fluide out to the radiator. When your automobile is standing still, everything is at ease, meaning not under the load of moving the mass of your ride. Now you all have just had a crash coarse in physics and fluide dynamics. I do hope you all have a better understanding in thermal dynamics as well. This how our world turns. Everyone would lost with out some kind of ride. Good Hunting and Have fun.