When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I'm sure this has been beat up... what's the common radiator cap used in warmer weather.
I just took my recently purchased 69 350/300 for a ride on the freeway for the first time, all went smooth watching all the guages, temp stayed around the 180ish mark throughout the drive, no concerns.
radiator was replaced with correct a few years ago and no reason to think there is a circulation issue.
about 10 minutes after getting home i seen a puddle of coolant around the passenger side front wheel, opened the hood and appears the overflow tank had purged coolant out of the overflow tube... looked like some drips right before the puddle which would indicate it was overflowing a bit as I pulled up.
I turned the key on and the temp guage went to about 190-200, definitely not overheat temp and the car fired right up, all this assuming the temp guage is accurate.
I am not sure if the coolant was over filled prior to my purchase, I am not sure if the cap is bad but I'm gonna replace it as a precaution, it is currently 15lb, should I be going slightly higher? Edit
15lb's is about right. Purging coolant when hot is much more likely an overfilled system than a bad cap.
What is the coolant level when cold in the overflow tank? Should only be about 1/4 full.
Yes, that's to much. Of course it spit some out.
The level goes up when the coolant gets hot and expands. Then as the engine cools down the coolant gets pulled back into the radiator. This keeps air out of the system and your radiator full. Take out the excess coolant and you should be fine.
Yes, that's to much. Of course it spit some out.
The level goes up when the coolant gets hot and expands. Then as the engine cools down the coolant gets pulled back into the radiator. This keeps air out of the system and your radiator full. Take out the excess coolant and you should be fine.
thanks again... was hoping so, will just let it come out as it needs now
Original radiators had a indicator of proper fill level on the passengers side of the tank when cold. If you are above the line it will purge the over fill when shut down. here an original line location.
Original radiators had a indicator of proper fill level on the passengers side of the tank when cold. If you are above the line it will purge the over fill when shut down. here an original line location.
thank you, my radiator is in only serviceable at the overflow tank, not at the radiator
I have a BB, so the configuration is a little different, but basically works the same. I belong to NCRS, but my car will not be a "Top Flight" car and I am in the process of adding an overflow bottle into the space below the factory tank so that any excess antifreeze goes into the bottle and then when the engine cools is sucked back into the tank. I just replaced my thermostat and getting the water level back to where it needs to be is a pain as you cannot fill the radiator easily and need to fill the overflow tank, run the car to operating temp and then cool down and add more water to the tank until it finds it correct level. In the process the air being forced out of the system dumps antifreeze onto the ground. I have no idea why they didn't install a catch bottle at the factory.
I have a BB, so the configuration is a little different, but basically works the same. I belong to NCRS, but my car will not be a "Top Flight" car and I am in the process of adding an overflow bottle into the space below the factory tank so that any excess antifreeze goes into the bottle and then when the engine cools is sucked back into the tank. I just replaced my thermostat and getting the water level back to where it needs to be is a pain as you cannot fill the radiator easily and need to fill the overflow tank, run the car to operating temp and then cool down and add more water to the tank until it finds it correct level. In the process the air being forced out of the system dumps antifreeze onto the ground. I have no idea why they didn't install a catch bottle at the factory.
Thank you, I do believe my level in the tank is a bit too high but gonna let it purge out as I drive it... I went through this a few years ago with a Viper that had air trapped in an upper hose, was a poor design, hard to get the air out and an overflow tank in the front bumper... don't believe I have air in this system just perhaps a little overfill before I purchased the car.
By the way, what you have is an expansion tank, not an overflow tank. An expansion tank is part of the pressurized cooling system (you can consider it an extension of the radiator) and must not be filled to the top unless there is also an overflow tank installed. Exactly like those OEM radiator pictures above that indicate a cold fill level. Expansion tanks have a pressurized radiator cap.
An overflow tank is an unpressurized container that will catch the overflow when hot and then feed the overflow back in when the system cools. Later C3s had a radiator cap on the radiator and overflow tanks. There may have been an early-70s environmental regulation, because around that time all new cars came with overflow tanks to prevent belching of coolant onto the ground. C4s have both an expansion tank and an overflow tank.
By the way, what you have is an expansion tank, not an overflow tank. An expansion tank is part of the pressurized cooling system (you can consider it an extension of the radiator) and must not be filled to the top unless there is also an overflow tank installed. Exactly like those OEM radiator pictures above that indicate a cold fill level. Expansion tanks have a pressurized radiator cap.
An overflow tank is an unpressurized container that will catch the overflow when hot and then feed the overflow back in when the system cools. Later C3s had a radiator cap on the radiator and overflow tanks. There may have been an early-70s environmental regulation, because around that time all new cars came with overflow tanks to prevent belching of coolant onto the ground. C4s have both an expansion tank and an overflow tank.
great and thank you, thanks to all that replied, good info as always
Since you did not specify if your 300 HP was with or with A/C. So it is good to indicate what setup you have for your Corvette help make for a good answers.
Since you did not specify if your 300 HP was with or with A/C. So it is good to indicate what setup you have for your Corvette help make a good answers.
Radiator cap question
