How to control cabin heat?
Thread Starter
Racer
Joined: Jan 2007
Posts: 385
Likes: 3
From: RTP NC
How to control cabin heat?
Finally got my '76 on the road!!
I noticed that heat was coming out of the vents. I don't have the heater core hoses connected and I thought that I could control the heat somewhat by changing the Climate Control to MAX/AC which would close the outside vent (would not let fresh air into the car). This didn't seen to chage the amount of heat coming from the vents. Any ideas?
I don't have carpet... or basically anything in the interior with the exception of the dash and the drivers seat so I was expecting it to be a little warm but....
Thanks,
I noticed that heat was coming out of the vents. I don't have the heater core hoses connected and I thought that I could control the heat somewhat by changing the Climate Control to MAX/AC which would close the outside vent (would not let fresh air into the car). This didn't seen to chage the amount of heat coming from the vents. Any ideas?
I don't have carpet... or basically anything in the interior with the exception of the dash and the drivers seat so I was expecting it to be a little warm but....
Thanks,
Burning Brakes
Joined: Oct 2006
Posts: 1,044
Likes: 0
From: Henrico VA
Racer
Joined: Mar 2006
Posts: 326
Likes: 0
From: Rochester New York
I was having huge heat problems too, this forum was a big help in doing a couple things - first, I put in a couple shut-off valves in the heater lines (you said your core is diconnected anyway, so nevermind that one), then heat still radiated into the cabin, so I disconnected the power to the blower motor, and heat still came in from the vents, so I got frustrated and ghetto-taped the vent openings shut.
If you have carpet and such out of it, now would be the best time to install some sort of heat-barrier to the firewall, trans tunnel, and floors. I wish I had done it when I was putting mine together, and now look at
me - ghetto-taping stuff
If you have carpet and such out of it, now would be the best time to install some sort of heat-barrier to the firewall, trans tunnel, and floors. I wish I had done it when I was putting mine together, and now look at
me - ghetto-taping stuff
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Check out the vac switch in the console as mentioned above. One of the devices that operates is the outside air door on the pass side of the wiper tray. Behind the screen is a vac operated flapper, vac applied it is supposed to close off. The vac comes from the vac switch, thru the gromet on the firewall, back thru a hole into the tray and then to the door operator. Would be a good time as mentioned above to fix all them lil gizmos and close up the leaks in the ducts. Do yo have AC? Does it work?
Racer
Joined: Mar 2006
Posts: 326
Likes: 0
From: Rochester New York
Uh oh, what does AC not being hooked up have to do with it?
Also, if his heater core was bypassed/not connected, and that little flapper dealie was open, would the result be engine compartment heat rolling into the cabin thru the open port?
PS - I only used tape because I was in a hurry...
Also, if his heater core was bypassed/not connected, and that little flapper dealie was open, would the result be engine compartment heat rolling into the cabin thru the open port?
PS - I only used tape because I was in a hurry...
Burning Brakes
Joined: Oct 2006
Posts: 1,044
Likes: 0
From: Henrico VA
If you can hear vacuum leaks right after you shut your car off (hissing air), then try to pinpoint those hoses and fix them. If it's not a leak, then make sure you have a vacuum line connected to your carburetor and follow it to see if looks good. You should have a vacuum reservoir, lines going to your lights, and lines going into your firewall. Maybe we can end up fixing some of this stuff while we're working on your vents.
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Uh oh, what does AC not being hooked up have to do with it?
Also, if his heater core was bypassed/not connected, and that little flapper dealie was open, would the result be engine compartment heat rolling into the cabin thru the open port?
PS - I only used tape because I was in a hurry...
Also, if his heater core was bypassed/not connected, and that little flapper dealie was open, would the result be engine compartment heat rolling into the cabin thru the open port?
PS - I only used tape because I was in a hurry...
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Drifting
Joined: Nov 2005
Posts: 1,795
Likes: 1
on my 78 i didnt have to put extra valves
after reading on the list here i checked and found
that my shut off valve was not holding vacuum.
bought a replacement and that took care of about
70% of the problem.
the second fix i did was the actualy vacuum switch
under the dash located in the heater box, i got to mine
by removing the glove box,
i found that it had slipped over the years and the cable
when put to the cold position was not fully turing to cold
i re-adjusted it so once in cold position it is fully off.
had the car out monday when it was 83 here and it was a pleasure
to drive.
after reading on the list here i checked and found
that my shut off valve was not holding vacuum.
bought a replacement and that took care of about
70% of the problem.
the second fix i did was the actualy vacuum switch
under the dash located in the heater box, i got to mine
by removing the glove box,
i found that it had slipped over the years and the cable
when put to the cold position was not fully turing to cold
i re-adjusted it so once in cold position it is fully off.
had the car out monday when it was 83 here and it was a pleasure
to drive.
Thread Starter
Racer
Joined: Jan 2007
Posts: 385
Likes: 3
From: RTP NC
Yeah, I do have A/C and it is not working. I'm pretty sure that all the vacuum lines are OK... and I just fixed the valves at the kick panel and outside so I know they are working. The engine is running smooth so I assumed that all the lines under the hood were OK. I can double check that...
Le Mans Master
Joined: Jan 2006
Posts: 9,192
Likes: 27
From: Boca Raton Florida
Well, sounds like you need to get in there and make sure you have vac at all the doors (4 on my car) when your supposed to. There are 2 that close off the outside air, the one for outside air and the one in the pass side kick panel
Safety Car
Joined: Jun 2002
Posts: 4,756
Likes: 2,505
From: Buckeye, AZ
St. Jude Donor '12-'13
When I replace my carpet I added Reflectix underneath......big help. Also many of the guys in our club put in a shutoff valve in the heater core hose, another big help. Corvettes all run hot, so you kind of get used to it a bit! You ought to ride in a mid-year!
