Real 3/4" shut off valve
Race Director
Joined: Oct 2008
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From: Long Island
1972 Corvettes did not have a WATER SHUT OFF VALVE.
Shut off the manifold to the heater line and you will not have any pressure in the heater core other than radiator pressure.
As an engineer I would only shut off one side. The fluid in the radiator core will expand as the firewall heats up and cool if there is A/C. Thus creating both vacuum and pressure in the heater core.
Shut off the manifold to the heater line and you will not have any pressure in the heater core other than radiator pressure.
As an engineer I would only shut off one side. The fluid in the radiator core will expand as the firewall heats up and cool if there is A/C. Thus creating both vacuum and pressure in the heater core.
