1964 radiator

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Apr 18, 2020 | 04:58 PM

565758

Thread Starter

Racer

Joined: Jul 2011

Posts: 498

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From: North Florida

1964 radiator

Looking for some advice. My 1964 corvette has an aftermarket radiator with a radiator cap rated at 15lbs. The expansion tank is also hooked up and has a cap rated at 7lbs. Factory configuration should only have one 307, 13lb cap on the expansion tank. How do I know that my coolant system is working correctly with 2 caps? Thanks in advance for any guidance.

Apr 18, 2020 | 05:05 PM

65hihp

Le Mans Master

Joined: Mar 2009

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From: Cold Harbor, VA

It's not. The correct radiator for your car is aluminum, has no side tanks, no cap, and no way to fill. You fill from the expansion tank. Right now, with a 15 lb cap on your radiator, it is as if there was no cap in your radiator. Pressure should never reach 15lbs. Ditch your copper radiator, get the good DeWitts Aluminum, and whistle merrily as you drive down the road with your motor running nice and cool.
And put the correct 307 13 lb AC cap on your expansion tank.

Apr 18, 2020 | 05:31 PM

Dave64

Drifting

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I don't know if it would be a stretch for your budget, but, in the long run, the DeWitts Aluminum direct replacement radiator and correct AC cap on the expansion tank is the way to go. Unless you have other issues, such as wrong fan, no fan clutch, bad water pump, or wrong/bad/no thermostat, you should have no cooling issues.

Apr 18, 2020 | 05:43 PM

565758

Thread Starter

Racer

Joined: Jul 2011

Posts: 498

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From: North Florida

I am troubleshooting a lot on this car at the moment. Cooling seems to be okay at the moment with the 2 caps and temp gauge reading, but need to test more. If it stays cool after I trouble shoot a bit more, would it be okay to leave as is? More than likely will go with the new DeWitts radiator to eliminate any issues in the future. Thanks for the help!

Apr 18, 2020 | 06:52 PM

Easy Rhino

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From: Middle TN by way of KY, OH, VA, IL, CA, FL, NY, SC, HI

Quote:

Originally Posted by 565758

A Dewitt's radiator is the permanent 4.00 solution, assuming everything is correct with your cooling system. However, if your current system is keeping your engine adequately cooled it can be a short term to medium term solution. Your 15 pound cap riding on your current radiator is just along for the ride, i.e., it's doing nothing as the 7 pound cap is going to open first in the event of an overheat situation.

Last edited by Easy Rhino; Apr 18, 2020 at 06:53 PM.

Apr 18, 2020 | 06:55 PM

Frankie the Fink

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Army

Quote:

Originally Posted by 565758

If it runs cool with what you have then its up to you to change up to a DeWitts (which I also run) and spend the big $$$ for the best...its not a necessity functionally.

Apr 18, 2020 | 07:03 PM

Railroadman

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From: Rochester NY

St. Jude Donor '09 thru '26

Let me second the motions made above:

1. If everything is functioning fine now, no need to make a panic purchase of something different

2. If you do change, Dewitt's is very well thought of here. I have one on my '92 and it has been excellent.