C2 Cooling System Help Please
07-30-2014, 02:56 PM
#1
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C2 Cooling System Help Please
I have a '66 project Vette that I just put an engine into and I also installed a new heater core, Griffin aluminum radiator, expansion tank, and cap. The problem is I don't know the routing of all the hoses. The upper and lower radiator hoses were obvious, but all the hoses going from the engine/water pump/manifold through the expansion/fill tank and into the heater core are a complete mystery. The manifold is an Edelbrock Performer with lots of plugged ports; I'm guessing to give options, but I believe one of them is supposed to accept a line either to or from the heater core. There is also plug on the top backside (angled) that I am pretty sure runs back to the core. Maybe one is out and one is a return. The engine is a mid-90's Vortec motor. As an aside, there is not a radiator fill cap on the top of a radiator (the stock and after market Griffin radiators don't have them); it appears that the design/intent is for me to fill the engine's coolant via the expansion tank. Any assistance with getting the routing correct would be fantastic (I like links to diagrams also). And thanks.
07-30-2014, 04:18 PM
#2
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I have a '66 project Vette that I just put an engine into and I also installed a new heater core, Griffin aluminum radiator, expansion tank, and cap. The problem is I don't know the routing of all the hoses. The upper and lower radiator hoses were obvious, but all the hoses going from the engine/water pump/manifold through the expansion/fill tank and into the heater core are a complete mystery. The manifold is an Edelbrock Performer with lots of plugged ports; I'm guessing to give options, but I believe one of them is supposed to accept a line either to or from the heater core. There is also plug on the top backside (angled) that I am pretty sure runs back to the core. Maybe one is out and one is a return. The engine is a mid-90's Vortec motor. As an aside, there is not a radiator fill cap on the top of a radiator (the stock and after market Griffin radiators don't have them); it appears that the design/intent is for me to fill the engine's coolant via the expansion tank. Any assistance with getting the routing correct would be fantastic (I like links to diagrams also). And thanks.
There's a 5/8" hose that runs from a fitting at the right front corner of the intake manifold back to the lower nipple on the heater core.
There's a 3/4" hose that runs from the upper nipple on the heater core forward to a zinc-plated "tee" that connects via a short 3/4" hose with two screw clamps to the elbow on the bottom of the expansion tank, and from the front of the tee to a fitting at the water pump inlet.
There are two hoses at the top of the expansion tank - the top one, directly under the fill cap, is an overflow, and its thin-wall hose just hangs straight down and stops at about the bottom of the frame. The next one down, on the tank itself, is the balance hose, and is under system pressure - it connects (with screw clamps) to the expansion tank nipple and to the nipple at the top right of the radiator - it routes outboard of the hood support base to the radiator.
When you fill the system, don't overfill the expansion tank - it should only be half-full with a cold engine.
Photo below shows the hose routings, and the link will take you to a photo feature article that explains how the Corvette cooling system works, how to diagnose it, and how to maintain it.
