How to stop Heat.
Thread Starter
Heel & Toe
Joined: Apr 2014
Posts: 24
Likes: 0
How to stop Heat.
Ok so my corvette spits alot of heat into the cabin. The button on my dash that controls the valve that shuts off the coolant valve that directs into heating system doesn't work. So what I did was dis-attach the little tube that powers the vacuum valve that stops the heated coolant from heating the heater core.
This did improve things significantly, heat going into the car use to be after a few minutes. Now it takes about 20 minutes of moderate driving or withing 5 minutes of hard core pushing the rpm at every green light. The heat is coming out every vent. Is there a quick fix that just removes the heat? I don't need to fix the heating system right now i just need a way to temporary shut it off.
Is there any other way heat is coming in? When I don't turn fans on the heat is ambivalently coming from the feet area. When i turn the fans on heat poors out every vent.
This did improve things significantly, heat going into the car use to be after a few minutes. Now it takes about 20 minutes of moderate driving or withing 5 minutes of hard core pushing the rpm at every green light. The heat is coming out every vent. Is there a quick fix that just removes the heat? I don't need to fix the heating system right now i just need a way to temporary shut it off.
Is there any other way heat is coming in? When I don't turn fans on the heat is ambivalently coming from the feet area. When i turn the fans on heat poors out every vent.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
The search button is your friend. There are many threads about cabin heat.
In short, there is No simple easy solution to eliminating it.
In short, if you put in a shut off valve on the hot water line that helps, thats the easiest partial fix.
Next, is stripping the interior and applying heat barriers of many types: neoprene, ceramic mat, dynomat, reflectix, lizard skin etc...
Rebuilding the duct doors, outside air valve etc, is also good stuff to do..
Wrapping the exhaust helps...
Lot of work, worth it to do all the above
In short, there is No simple easy solution to eliminating it.
In short, if you put in a shut off valve on the hot water line that helps, thats the easiest partial fix.
Next, is stripping the interior and applying heat barriers of many types: neoprene, ceramic mat, dynomat, reflectix, lizard skin etc...
Rebuilding the duct doors, outside air valve etc, is also good stuff to do..
Wrapping the exhaust helps...
Lot of work, worth it to do all the above
Le Mans Master
Joined: Oct 2007
Posts: 7,445
Likes: 971
From: Tennessee/Rhode Island
Three steps:
1. remove vacuum heater control valve and replace with a manual shutoff valve-home Depot, Lowes, etc. No hot water will go to the Heater core-important!
2. Locate wiring for the blower motor which runs continuously and pull the harness out of the relay under the hood (on my 78). Shuts the motor from running continuously even in the "off" position.
3. Home Depot/Lowes again-But a roll of Reflectix and remove all interior carpeting and put reflectix on the floor and carpeting over the reflectix.
If you do all 3 items, you will reduce hot engine heat from entering the cabin by 90%.
1. remove vacuum heater control valve and replace with a manual shutoff valve-home Depot, Lowes, etc. No hot water will go to the Heater core-important!
2. Locate wiring for the blower motor which runs continuously and pull the harness out of the relay under the hood (on my 78). Shuts the motor from running continuously even in the "off" position.
3. Home Depot/Lowes again-But a roll of Reflectix and remove all interior carpeting and put reflectix on the floor and carpeting over the reflectix.
If you do all 3 items, you will reduce hot engine heat from entering the cabin by 90%.
Racer
Joined: May 2011
Posts: 373
Likes: 6
From: Dover Delaware
Three steps:
1. remove vacuum heater control valve and replace with a manual shutoff valve-home Depot, Lowes, etc. No hot water will go to the Heater core-important!
2. Locate wiring for the blower motor which runs continuously and pull the harness out of the relay under the hood (on my 78). Shuts the motor from running continuously even in the "off" position.
3. Home Depot/Lowes again-But a roll of Reflectix and remove all interior carpeting and put reflectix on the floor and carpeting over the reflectix.
If you do all 3 items, you will reduce hot engine heat from entering the cabin by 90%.
1. remove vacuum heater control valve and replace with a manual shutoff valve-home Depot, Lowes, etc. No hot water will go to the Heater core-important!
2. Locate wiring for the blower motor which runs continuously and pull the harness out of the relay under the hood (on my 78). Shuts the motor from running continuously even in the "off" position.
3. Home Depot/Lowes again-But a roll of Reflectix and remove all interior carpeting and put reflectix on the floor and carpeting over the reflectix.
If you do all 3 items, you will reduce hot engine heat from entering the cabin by 90%.
Great post you did. I also have a 78 and would like to know if you could send me a pic of your #2 fix.....
Appreciate your help...
mk's78 aka Mike
email is mkane25@verizon.net
thx........
Le Mans Master
Joined: Oct 2007
Posts: 7,445
Likes: 971
From: Tennessee/Rhode Island
Good morning jb78L-82,
Great post you did. I also have a 78 and would like to know if you could send me a pic of your #2 fix.....
Appreciate your help...
mk's78 aka Mike
email is mkane25@verizon.net
thx........
Great post you did. I also have a 78 and would like to know if you could send me a pic of your #2 fix.....
Appreciate your help...
mk's78 aka Mike
email is mkane25@verizon.net
thx........
Mike,
The wires go into 2 relays on the 78 in the location of the picture. The bottom relay is the one that controls the fan-just pull the plug out and the motor will stop running continuously. Let us know how you make out.
Last edited by jb78L-82; Aug 4, 2014 at 09:25 AM.
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Safety Car
Joined: Mar 2007
Posts: 3,518
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Ok so my corvette spits alot of heat into the cabin. The button on my dash that controls the valve that shuts off the coolant valve that directs into heating system doesn't work. So what I did was dis-attach the little tube that powers the vacuum valve that stops the heated coolant from heating the heater core.
This did improve things significantly, heat going into the car use to be after a few minutes. Now it takes about 20 minutes of moderate driving or withing 5 minutes of hard core pushing the rpm at every green light. The heat is coming out every vent. Is there a quick fix that just removes the heat? I don't need to fix the heating system right now i just need a way to temporary shut it off.
Is there any other way heat is coming in? When I don't turn fans on the heat is ambivalently coming from the feet area. When i turn the fans on heat poors out every vent.
This did improve things significantly, heat going into the car use to be after a few minutes. Now it takes about 20 minutes of moderate driving or withing 5 minutes of hard core pushing the rpm at every green light. The heat is coming out every vent. Is there a quick fix that just removes the heat? I don't need to fix the heating system right now i just need a way to temporary shut it off.
Is there any other way heat is coming in? When I don't turn fans on the heat is ambivalently coming from the feet area. When i turn the fans on heat poors out every vent.
Putting in a manual valve on one of the hoses is a good place to start.
Last edited by minitech; Aug 4, 2014 at 06:20 PM.
Instructor
Joined: Nov 2011
Posts: 234
Likes: 24
From: Warsaw Ohio
Install a shutoff valve on both heater hoses I used these from e-bay , well built should outlast the Car and CHEAP . You'll need one of each 5/8 and 3/4 . Under $20 for the pair shipped.
http://www.ebay.com/itm/350291866504?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT#ht_189wt_1314
http://www.ebay.com/itm/3-4-NOMINAL-Barb-x-Barb-Ball-Valve-Brass-Ball-Valve-Full-Port-600WOG-/140903569368?pt=LH_DefaultDomain_0&hash=item20ce81d7d8#ht_311wt_1314
http://www.ebay.com/itm/350291866504?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT#ht_189wt_1314
http://www.ebay.com/itm/3-4-NOMINAL-Barb-x-Barb-Ball-Valve-Brass-Ball-Valve-Full-Port-600WOG-/140903569368?pt=LH_DefaultDomain_0&hash=item20ce81d7d8#ht_311wt_1314
Le Mans Master
Joined: Oct 2007
Posts: 7,445
Likes: 971
From: Tennessee/Rhode Island
Melting Slicks
Joined: Jul 2009
Posts: 2,091
Likes: 40
In 1981 I owned a nearly new factory BLaCK 1979 L82 with glass mirrored tops. Beautiful car ......spoilers, alum wheels ..the works ....
I lived in the south at the beach then too.
Let me tell you .....without AC you could have passed out from heat in August. That's the hottest corvette I've ever been in .
The bottoms of my sneakers felt sticky the floor board was so hot in the summer especially .
I think that car ran a temp of 225 or 230 .....I never saw the thing under 200 degrees .
They were hot foot cars new
I lived in the south at the beach then too.
Let me tell you .....without AC you could have passed out from heat in August. That's the hottest corvette I've ever been in .
The bottoms of my sneakers felt sticky the floor board was so hot in the summer especially .
I think that car ran a temp of 225 or 230 .....I never saw the thing under 200 degrees .
They were hot foot cars new
Le Mans Master
Joined: Oct 2007
Posts: 7,445
Likes: 971
From: Tennessee/Rhode Island
In 1981 I owned a nearly new factory BLaCK 1979 L82 with glass mirrored tops. Beautiful car ......spoilers, alum wheels ..the works ....
I lived in the south at the beach then too.
Let me tell you .....without AC you could have passed out from heat in August. That's the hottest corvette I've ever been in .
The bottoms of my sneakers felt sticky the floor board was so hot in the summer especially .
I think that car ran a temp of 225 or 230 .....I never saw the thing under 200 degrees .
They were hot foot cars new
I lived in the south at the beach then too.
Let me tell you .....without AC you could have passed out from heat in August. That's the hottest corvette I've ever been in .
The bottoms of my sneakers felt sticky the floor board was so hot in the summer especially .
I think that car ran a temp of 225 or 230 .....I never saw the thing under 200 degrees .
They were hot foot cars new
My 78 L-82 4 speed when new ran 225 in the Cold weather and 235-245 with A?C on in the summer. By the time i was done changing everything, eliminating emissions, changing the tuning, upgrading the cooling system, the car ran 175-180, tops 185 before this Springs total rebuild/upgrade. Car has easy 100+ more HP and runs 175-180 even now. They were setup to run hot from the factory, only to pass emissions but they were HOT back then-ridiculous actually.
Melting Slicks
Joined: Jul 2009
Posts: 2,091
Likes: 40
Absolutely true!!
My 78 L-82 4 speed when new ran 225 in the Cold weather and 235-245 with A?C on in the summer. By the time i was done changing everything, eliminating emissions, changing the tuning, upgrading the cooling system, the car ran 175-180, tops 185 before this Springs total rebuild/upgrade. Car has easy 100+ more HP and runs 175-180 even now. They were setup to run hot from the factory, only to pass emissions but they were HOT back then-ridiculous actually.
My 78 L-82 4 speed when new ran 225 in the Cold weather and 235-245 with A?C on in the summer. By the time i was done changing everything, eliminating emissions, changing the tuning, upgrading the cooling system, the car ran 175-180, tops 185 before this Springs total rebuild/upgrade. Car has easy 100+ more HP and runs 175-180 even now. They were setup to run hot from the factory, only to pass emissions but they were HOT back then-ridiculous actually.
Odd .....I traded a bone stock red 78 auto L48 corvette for that Black L82 car....... The 78 was no where as hot overall to me as the 79 L82 car.
Matter fact ....that little red 78 L48 may have been the best behaved, reliable , worry free , nothing broke the whole time I owned her. Used zero oil....AC worked fantastic , cruise , everything perfect .
The desire to shift gears overcame me in the end.
Last edited by LS4 PILOT; Aug 7, 2014 at 07:42 PM.
Burning Brakes
Joined: Sep 2009
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From: hickory NC
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originally posted byjb78L-82
1. remove vacuum heater control valve and replace with a manual shutoff valve-home Depot, Lowes, etc. No hot water will go to the Heater core-important!
2. Locate wiring for the blower motor which runs continuously and pull the harness out of the relay under the hood (on my 78). Shuts the motor from running continuously even in the "off" position.
3. Home Depot/Lowes again-But a roll of Reflectix and remove all interior carpeting and put reflectix on the floor and carpeting over the reflectix.
1. remove vacuum heater control valve and replace with a manual shutoff valve-home Depot, Lowes, etc. No hot water will go to the Heater core-important!
2. Locate wiring for the blower motor which runs continuously and pull the harness out of the relay under the hood (on my 78). Shuts the motor from running continuously even in the "off" position.
3. Home Depot/Lowes again-But a roll of Reflectix and remove all interior carpeting and put reflectix on the floor and carpeting over the reflectix.
Wife no longer complains about the heat.
Le Mans Master
Joined: Oct 2007
Posts: 7,445
Likes: 971
From: Tennessee/Rhode Island
Yes.....I was just a kid going to college ....it was bone stock......it would get so hot the waves of heat poured off the top of that black hood . Remember thinking ....is this car going to melt or catch on fire ....LOL....I was just a kid....
Odd .....I traded a bone stock red 78 auto L48 corvette for that Black L82 car....... The 78 was no where as hot overall to me as the 79 L82 car.
Matter fact ....that little red 78 L48 may have been the best behaved, reliable , worry free , nothing broke the whole time I owned her. Used zero oil....AC worked fantastic , cruise , everything perfect .
The desire to shift gears overcame me in the end.
Odd .....I traded a bone stock red 78 auto L48 corvette for that Black L82 car....... The 78 was no where as hot overall to me as the 79 L82 car.
Matter fact ....that little red 78 L48 may have been the best behaved, reliable , worry free , nothing broke the whole time I owned her. Used zero oil....AC worked fantastic , cruise , everything perfect .
The desire to shift gears overcame me in the end.