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-   -   67 AC/Heater ???????'s (

rico0004 07-07-2012 08:05 PM

67 AC/Heater ???????'s
Hello Everyone,
Really excited about finding this site. I got a 67 C10 LB w/ sm back window. Been working on it for about 4 months now. The guy i got it from basically just cut everything out and started tearing down the truck. I now got the truck running finally. Just have to fix heat issue and temp guage, and everything will be working correctly agian. So I have slowly been learning all kinds of new stuff. It was originally a AC truck. Now has early 70's 305 in it. Ac compressor was deleted, and nothing was wired or hooked up. I just want to make sure the truck has heat/defrost, not worried about AC for now. I found a wiring diagram, and now have it blowing out of the box. MY problem is no vent/defrost hoses in place, so i don't know which hose is supposed to go were? and which port on box? I know outside air is controlled with vacuum. Of course no vac hoses any where. Does anyone know of a good site, i can get a diagram on vacuum lines, and something showing me what vent/defrost hoses go where? I would GREATLY appreciate any advice of what i need to do or unhook to make sure truck just has heat/defrost outside vent/air, and doesn't burn down. LOL I know probally sounds lil dumb. I can turn a wrench, but wouldn't call myself no master mec....

A big TY to everyone for there time..

Tinkermc 07-07-2012 09:31 PM

Re: 67 AC/Heater ???????'s
welcome to the forum, even though I can't answer your question this is one of the most knowledgeable places you have ever been. Someone will be able to help you.

bonnieclyde100 07-08-2012 12:51 AM

Re: 67 AC/Heater ???????'s
1 Attachment(s)
here is a picture of the vacuum diagram. as far as what vent the air comes from is controled by cables.

rico0004 07-08-2012 06:29 PM

Re: 67 AC/Heater ???????'s
AWESOME!!! that will sure help alot. My vacum head on top of the heater controll box, only has two ports? Can i just use this diagram and hook one of the line in with a t-valve? Do I need to hook up the vacum lines to have heat and defrost?I rebuilt the box, putting in new levers, and 3 new cables. I know one cable goes thru fire wall, and hooks to a lever on top. I think one hooks to the vent port passenger door? Anyone know where the other one goes?

TY for the replys... Keep the Chevy Dream Alive!!!

aussiejohn 07-08-2012 08:17 PM

Re: 67 AC/Heater ???????'s

Welcome aboard! I'll be keeping an eye on this thread, as I have a '67 GMC pickup that was built with the 351 engine. It was sold to me with an HEI 350 and has just a heater, but I haven't seen any vacuum pieces. One of the levers was broken and I bought a complete new AC console from Classic when I was in CA last year.

I have yet to fit it and connect to the cables, but I'm sure the heater was working when I got it. I plan to fit AC when I have the time (Haha!), hence the AC console. Do I need any vacuum bits for the AC?

Regards from Down Under. :gmc2:


Tinkermc 07-08-2012 09:21 PM

Re: 67 AC/Heater ???????'s
I told you there were a lot of smart people here

Luis_gz06 07-08-2012 11:35 PM

Re: 67 AC/Heater ???????'s
Here's the link of the diagram with the two ports.

bonnieclyde100 07-09-2012 12:06 PM

Re: 67 AC/Heater ???????'s
you will need to know weather your water valve opens or closes with vacuum. if it opens with vacuum the T splitter will not work because it will make your vents work the opposite of what there supposed to. if it closes with vacuum the splitter will work. but if it is the wrong water valve you could always buy the write one.

rico0004 07-09-2012 03:24 PM

Re: 67 AC/Heater ???????'s
I can't THANK everyone enough for all the advice. I'm so glad I found this site....

ole dollor 07-09-2012 10:55 PM

Re: 67 AC/Heater ???????'s
welcome to the board....good luck on your build....have fun with to love these old chevy's....

rico0004 07-13-2012 06:22 PM

Re: 67 AC/Heater ???????'s
1 Attachment(s)
Can anyone tell me or got a diagram for the AC/Heater Defrost Vent Hose goes? To which port on the box under dash? Also to which vent in the dash? Example defrost vents, Ac vents? Dash Vents? I really appreciate it? Just the info i have received so far from all you wonderful members of this site, as helped me accomplish a lot of progress.

bonnieclyde100 07-13-2012 11:19 PM

Re: 67 AC/Heater ???????'s
1 Attachment(s)
do you have pics of what you have because there are a few different setups in these trucks? some trucks have a AC vent above the radio and some dont.
here is a diagram of what i have.

rico0004 07-27-2012 12:27 PM

Re: 67 AC/Heater ???????'s
1 Attachment(s)
Can anyone perhaps tell me where these cables hook to on each end? I know how they hook to the heater control box, but no idea where they hook to on the heater box?

bonnieclyde100 07-27-2012 05:25 PM

Re: 67 AC/Heater ???????'s
the longest goes through the firewall out to the mixture flap and inside to the temp control lever usually on the bottom

the second longest goes from center lever to the flap control in the center section of the ac box that flap also hits the switch thats inside the airbox that turns on the ac compressor

the shortest goes from top lever(which controls defrost and floor heat) to the part of the ac box located right below the ac control to control the defrost.
hope this helps

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