Can somebody explain in detail how the coolant system works on our car??
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Can somebody explain in detail how the coolant system works on our car??
Ok guys, i'am wondering how the overflow tank works in our cars. You see when the car is running the dipsticks shows me that the coolant level is at full. Now when the engine is off, and i have let it sit for about 30 minutes, i check the overflow tank again and the dipstick gives me a reading blow the fmark, closer to the low mark. Now is it because the coolant gets sucked back into the radiator? Oh yeah when i open the coolant resevoir and put my nose up to the opening of the coolant resevoir, i can smell coolant, this is when the engine is warm. Can somebody please in detail explain how the coolant system works on this car, and what signs i should look for if there is a problem with the coolant system
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WWFSMD
Joined: Jun 2001
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From: SoCal
Most automotive cooling systems are about the same in their basic operation. Here's how they work:
Car gets hot, pressure builds up in the cooling system. When the pressure gets higher than the radiator cap (AST cap on stock FD) spring, some coolant flows out the tube to the overflow tank.
When the car cools down, some vacuum is created in the cooling system. The radiator cap has another little passage in it that opens under any vacuum condition, so coolant is sucked back into the motor from the overflow tank as it cools down.
Take a look at your radiator cap. It opens to let coolant out of the engine when the pressure overcomes the big spring on there. The coolant flows out of the engine between the rubber seal and the seat inside the filler neck. The second rubber seal that is right under the cap makes sure that the water flows out the overflow tube instead of just coming out around the edge of the cap.
In the middle of the radiator cap, there is a metal button that is about the size of a penny. Carefully pull the button out to see how it opens under vacuum. You can see that the button pulls out easily, and this means that it opens under any vacuum to pull some coolant back into the engine from the overflow tank. You can also imagine why any hole in the overflow tube makes your coolant run low in the engine -- coolant will come out under pressure, but with the hole you'll only suck air back into the engine as it cools.
-Max
Car gets hot, pressure builds up in the cooling system. When the pressure gets higher than the radiator cap (AST cap on stock FD) spring, some coolant flows out the tube to the overflow tank.
When the car cools down, some vacuum is created in the cooling system. The radiator cap has another little passage in it that opens under any vacuum condition, so coolant is sucked back into the motor from the overflow tank as it cools down.
Take a look at your radiator cap. It opens to let coolant out of the engine when the pressure overcomes the big spring on there. The coolant flows out of the engine between the rubber seal and the seat inside the filler neck. The second rubber seal that is right under the cap makes sure that the water flows out the overflow tube instead of just coming out around the edge of the cap.
In the middle of the radiator cap, there is a metal button that is about the size of a penny. Carefully pull the button out to see how it opens under vacuum. You can see that the button pulls out easily, and this means that it opens under any vacuum to pull some coolant back into the engine from the overflow tank. You can also imagine why any hole in the overflow tube makes your coolant run low in the engine -- coolant will come out under pressure, but with the hole you'll only suck air back into the engine as it cools.
-Max
WWFSMD
Joined: Jun 2001
Posts: 5,035
Likes: 4
From: SoCal
The overflow tank should not be sealed, and the tube inside it should go to the bottom, so that fluid is picked up when the engine starts sucking the coolant back into the engine. The overflow tank is like a drink with a straw in it.
-Max
-Max
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