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Hot Air At Feet



I have an 81 and when I am driving I get warm or hot air coming in at my feet. I am not running the air. I also have the fresh air turned off. Is this right?
Hot feet in my 79 too.. looking into insulation products ,Kool Mat, etc...I disconnected my heater hoses too...When its in the 90s everyday where does the heat from the motor go????:upthumbs
Every shark I have driven has had this problem, including my '78. The engine and tranny heat just comes through into the passenger compartment. The only thing I can suggest is some sort of insulation, or heat shield.

they make a fabric tape for insulating exhaust. try rapping some abound the exhaust where it is close to the interior or areas that get hot
My 80 is the same. Several options first- install manual shut-off valve in the heater hose line to stop flow to heater and into the car. You can buy this valve at any auto parts shop for a few bucks. Really cooled things down in my car. Second- the blower is always on even when turned off at the switch. You can disconnect one of the wires to stop the blower from running always. I am out of town but can send you more info when I return next week. By disconnecting this wire, the blower will only run when switched to the on position thus not blowing air in the off position.

If this works correctly, you see a link to my posting on corvette forum about the blower always running.http://www.corvetteforum.cc/ubb/Forum3/HTML/029578.html


blower wire

Thanks to all for the info.
Jim, I followed the link and the post on the blower wire. This sounds like the problem that I have and will start with it. Does the blower work when turned on after taking off the brown wire?
Here is a copy of some replys to this problem from the link.Thanks to all the guys that put these up.
I hope they do not mind me reposting.

To turn blower off instead of lowest speed: Locate under hood, on pass. side at blower resister box, the wire at bottomof 4 wire T nearest pass side, dk. brown on 77. One can disconnect & bend that one connecter down, & reconnect. This is fast & reverseable. Of course
you could remove wire from connecter, esp. if you will be doing this often.I started doing this years ago to save wear on blower motor, less noise w/ blower off & key on.Don't need low anyway!

You don't need to go through the hassle of plugging the heater core. for $10 at AutoZone, buy a generic in line shut off valve (all you need is the hose diameter). Splice into the heater hose running from the water pump. The valve has an on/off lever. Set it to off and stop the flow of water to the heater core. In the winter you can open the valve if you want. Simple solution but it will reduce cabin heat substantially. Worked for me.

While there's nothing wrong with any of the above suggestions, I'd like to make a plug here for originality and GM engineering. Your car has a water shutoff valve already (sometimes called "A/C water shutoff" or "hot water shutoff"). It's located near the bottom of the passenger side firewall, where the heater hose from the water pump goes through the firewall to the heater core. The valve has a vacuum line from the A/C controls that is used to control its open/closed status. Usually due to carbonate sediments in the cooling system, the little flapper valve inside this little jewel sticks open. It can also stick closed, but that's not nearly as common because it's in the closed position much less often. If you like the idea of having your car work as designed, you can get the valve from Zip or other suppliers for about $18. I have seen some of them
that just needed a good cleaning and a shot of WD-40 on the vacuum actuator, and it's always a possibility that the vacuum hose is cracked or has
slipped off the nipple
I think everybody here is on the right track.

However, I found something out recently that sheds new light on this problem.

Recently I have not only removed the entire cowl out of my car, but helped a friend do his and went to a scrap yard and inspected several other C3 carcuses.

Depending on the year models and options there is either one large cowl vent (new style with air), or two large cowl vents that are just forward of the a-pillar/hinge pillar.

Over time the rubber seal goes away leaving a huge gap around the door and housing. Hot air that comes off the motor and works around the firewall and cowl will pour straight through there on the occupants feet. Not good. That means that even with insulation, heat shut off, and the vent closed you will get hot air under the dash on the feet.

In my situation, I am running a vintage air super cooler II so those vents are no longer needed. Neither are the port holes just above that stay open all the time (about 2" in diameter on each side of the car). I removed the vent doors and upper ports and glassed them solid. This strengthened the cowl substantially and cut off all air movement into the cockpit from the engine and cowl.

The vintage air will simply recurculate the interior air.

Your option will be to also try to replace the rubber seal on the cowl vent and find a way to plug the two ports just above. Between this and the other suggestions there is no excuse for hot air to enter the car.
I don't know but when I push my function control (air, vent, heat) all the way to the left "off" the blower fan stops and I get no air flow through any vent. With the temp function control also pushed to the left "cold" I don't get hot air from my vents (when in vent mode) as this turns off the coolent flow to the heater. I think if your controls are working properly they should function as mine do.
With the temp function control also pushed to the left "cold" I don't get hot air from my vents (when in vent mode) as this turns off the coolent flow to the heater. I think if your controls are working properly they should function as mine do. [/B]

That is awesome.

I can only speak for the ones I have driven and worked on. It seems to me I have had the same experience as the others with the Shark body. However, I drove an 82 around during the summer time in Daytona beach back in 1987. The car was still pretty fresh. I don't remember that one making my feet hot. At that time I had a 74 model. You could roast hot dogs on the floorboard of that car.

I think it is a combination of everything working together like the factory intended to get it right. Good insulation, good seals on the vents and cowl, proper shut off valve, and functional control unit.

Your car is beautiful. Especially knowing it has frosty air inside.

Thanks for the kind words Chris, and yes with the air on it does get frosty inside.
I agree, everything has to be there and function properly for the interior to be comfortable. I also agree the earlier cars have a heat problem. A friend has a 69 and it is hotter than, well you know, with everthing working correctly. I just think from 80 on GM solved the interior heat problem.

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