heater core
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Joined: Oct 2009
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heater core
is it me? iv'e been dealing with a hotfoot for sometime now, floor is well insulated etc, after blocking off the intake to the heater core, I took the car for a ride, seems much cooler!! can't wait to go to the store and buy a 3/8 shutoff valve. hopefuly a nice brass one
Team Owner
Joined: Jan 2006
Posts: 37,637
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From: Crossville TN
Lowe's.... 3/8" brass, lever activated (90*) shut-off valve. Cut into either the IN or RETURN line from the heater core somewhere on the right inner fender. Put it somewhere near a hold-down clamp for that hose: close enough to do some good, but far enough from it to still be an easy install.
I painted my valve semi-flat black before installing. I left the lever the dark blue plastic, so that I could still find it!
It blends so well with the other hoses and semi-flat black surfaces that you really don't notice it.
I painted my valve semi-flat black before installing. I left the lever the dark blue plastic, so that I could still find it!
It blends so well with the other hoses and semi-flat black surfaces that you really don't notice it.
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Joined: Oct 2009
Posts: 54
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Lowe's.... 3/8" brass, lever activated (90*) shut-off valve. Cut into either the IN or RETURN line from the heater core somewhere on the right inner fender. Put it somewhere near a hold-down clamp for that hose: close enough to do some good, but far enough from it to still be an easy install.
I painted my valve semi-flat black before installing. I left the lever the dark blue plastic, so that I could still find it! It blends so well with the other hoses and semi-flat black surfaces that you really don't notice it.
I painted my valve semi-flat black before installing. I left the lever the dark blue plastic, so that I could still find it!
It blends so well with the other hoses and semi-flat black surfaces that you really don't notice it.I was thinking of just removing that and putting in the shut off valve> obviously that would disable it from controls>>>is this a mistake?
for the record this is a 76 and I have tried to stay as true to originil as possible(even kept the underpowered engine stock)
Drifting
Joined: Mar 2011
Posts: 1,886
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The 76's had a vacuum powered heater core shutoff valve. Maybe yours has failed. You should be able to just replace it, without "reengineering the wheel" with a big, bulky hardware store ball valve..
The heat level is controlled by an air flap inside the HVAC box.
The heat level is controlled by an air flap inside the HVAC box.
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Joined: Oct 2009
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Lots of good info! The only thing that I don't get is everyone says 3/8- my hose going into core is 5/8 and one coming out a little bigger. Plumbing 5/8 very rare. Bought a 3/4 ball that seems to fit nicely. Does anyone have a pic of where exactly that on off valve with the vacuum line mounts exactly. Previous owner had in just hanging. Thanks again for responding!
Racer
Joined: Jul 2010
Posts: 430
Likes: 31
From: Ontario
I put a 3/4 ball valve in each heater hose, took the levers off and stuck one of them in my road trip kit. You can see the valves if you're looking for them, otherwise they blend right in. Still gets a tad warm in the car from exhaust heat even with the windows down but a little AC takes care of that.
Btw, the reason I used two valves was actually my dog's fault. I said, "Do I need a ball valve in each hose Franky?" and he barked twice.
Btw, the reason I used two valves was actually my dog's fault. I said, "Do I need a ball valve in each hose Franky?" and he barked twice.
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Team Owner
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From: Southbound
Cruise-In II Veteran
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Joined: Oct 2009
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When I bought this car the previous owners had put somekind of ugly shut off valve overthere, we just threw it way during the restoration.......now I know what it was. I bought the 3/4 and taped off the handle and fitting ends and painted it flat black...looks good!
Drifting
Joined: Mar 2011
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Well, no. The heater is suppied by two different sized hoses, 5/8" ID and 3/4" ID.
Without facts, I am speculating that Chevrolet did it that way to insure the water will go through the core in a specific direction, likely bottom to top. Perhaps that will make it bleed air bubbles easier.
Without facts, I am speculating that Chevrolet did it that way to insure the water will go through the core in a specific direction, likely bottom to top. Perhaps that will make it bleed air bubbles easier.
Racer
Joined: Jul 2010
Posts: 430
Likes: 31
From: Ontario
The ball valves I used are compatible with threaded plastic nipples that are available in both 5/8 and 3/4 sizes. Use the correct size box end wrench on the nipples. An open end or an adjustable wrench will round them off. You have to fiddle with the nipples to get them started into the ball valve threads correctly. They're kinda devious.
Racer
Joined: Jul 2013
Posts: 385
Likes: 3
From: Leesburg VA
As an experiment today, I used a clamp to close off one of the heater hoses. It was hot in Northern Virginia today, and it was mighty hot in the Corvette as well. It might have been marginally cooler, but not the difference I was hoping for. Mine is comfortable at a stop light, but as soon as I start moving I can feel the heat coming in on my feet. Admittedly, my HVAC system is not working as designed at the moment, but I really thought the source of the majority of the heat was from the heater core.
Another project to add to my (growing) winter 2013/2014 overhaul.
John
Another project to add to my (growing) winter 2013/2014 overhaul.
John
Burning Brakes
Joined: Apr 2010
Posts: 1,018
Likes: 9
From: Winston Ga.
As an experiment today, I used a clamp to close off one of the heater hoses. It was hot in Northern Virginia today, and it was mighty hot in the Corvette as well. It might have been marginally cooler, but not the difference I was hoping for. Mine is comfortable at a stop light, but as soon as I start moving I can feel the heat coming in on my feet. Admittedly, my HVAC system is not working as designed at the moment, but I really thought the source of the majority of the heat was from the heater core.
Another project to add to my (growing) winter 2013/2014 overhaul.
John
Another project to add to my (growing) winter 2013/2014 overhaul.
John