Coolant levels in a 76
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In the reservoir. About a quarter full cold. No more or it will spit coolant on hills when hot.
Radiator, completely full right to the top. When hot the coolant expands and pushes fluid into the reservoir. As it cools down it pulls the fluid back into the radiator.
This keeps air out of the system. Air is bad.
Radiator, completely full right to the top. When hot the coolant expands and pushes fluid into the reservoir. As it cools down it pulls the fluid back into the radiator.
This keeps air out of the system. Air is bad.
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5th Gear
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In the reservoir. About a quarter full cold. No more or it will spit coolant on hills when hot.
Radiator, completely full right to the top. When hot the coolant expands and pushes fluid into the reservoir. As it cools down it pulls the fluid back into the radiator.
This keeps air out of the system. Air is bad.
Radiator, completely full right to the top. When hot the coolant expands and pushes fluid into the reservoir. As it cools down it pulls the fluid back into the radiator.
This keeps air out of the system. Air is bad.
Safety Car
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Also important is the correct radiator cap, normally a 15lb cap.
Also, if you remove the overflow bottle cap there should be a hose connected to the inner side of the cap.
This is both the relief and suction hose to and from the radiator.
The hose length should be off the bottom of the overflow bottle a inch or so.
The hose is not rubber but more like silicone...
Also, if you remove the overflow bottle cap there should be a hose connected to the inner side of the cap.
This is both the relief and suction hose to and from the radiator.
The hose length should be off the bottom of the overflow bottle a inch or so.
The hose is not rubber but more like silicone...
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Can't figure this one out: Put a new Dewitt's, correct radiator in my 82 Collector Edition. Burped the system properly. Overflow reservoir is at the proper level when cold. Radiator has correct 15 PSI cap. Car runs nice and cool. No leaks. Every single time I open the radiator cap when cold, anti freeze flows out even though I have suctioned it down 4 times to well below the cap area? Why is this backing up that high into the radiator???
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It won't overflow immediately after siphoning. I close the cap after siphoning it down and take it for a ride. Let it sit overnight. The following morning I open the cold radiator cap and anti freeze flows out. Once again it's overfull. I siphon it again and repeat the whole process. It is still over full, yet the coolant overflow tank is right on the cold line as it should be.
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It won't overflow immediately after siphoning. I close the cap after siphoning it down and take it for a ride. Let it sit overnight. The following morning I open the cold radiator cap and anti freeze flows out. Once again it's overfull. I siphon it again and repeat the whole process. It is still over full, yet the coolant overflow tank is right on the cold line as it should be.
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Maybe I'm chasing an issue that doesn't exist. Runs nice and cool. Guess I'll stop chasing my tail and not open the radiator cap any more.
Thanks.
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I've had alot of Corvettes and never had one that would spill over every time you opened the radiator cap, cold. I always kept them a couple of inches from the top and that's where it stayed. Agree with you that the overflow tank is higher. Guess it's the seesaw effect transferring fluid back and forth depending on whether it's hot or cold.
Maybe I'm chasing an issue that doesn't exist. Runs nice and cool. Guess I'll stop chasing my tail and not open the radiator cap any more.
Thanks.
Maybe I'm chasing an issue that doesn't exist. Runs nice and cool. Guess I'll stop chasing my tail and not open the radiator cap any more.
Thanks.
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I agree with you Mel. My older Vettes have expansion tanks with no caps on the radiators. Expansion tanks kept 1/2 full.
I'm not opening the radiator cap any more.
I'm not opening the radiator cap any more.