A/C to Non-A/C Conversion

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Powerhouse Ranch

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I've mentioned it a bit around already, but i am deleting the AC system entirely and installing a factory GM heater box in the Jimmy. It's going to be a summer beast with the top off, i won't need AC. Plus more room under the hood. . . ANYWAYS i had just bought a heater box and heating control switches off of eBay for a decent deal. Tonight i had just ripped off all the major AC components. Now the next step, how am i to patch the firewall? Now i know they sell the panels but the majority i found were entire heater AC delete? So then say i do get one and put it on i'll have to cut new holes for the heater core, etc.

So what i'm getting at here, is any help/notes on this would be awesome. I want to get this as close as factory as i can (except with firewall patch) and could use any photos/thoughts. My dad's '87 is the same exact setup; 350 SBC with non-AC setup. I was comparing side by side but he is using it indefinitely (rightfully so, it's his!)

Couple quick questions on top of my head, what patch piece would work for this, what did GM use to seal everything back up to the firewall (or have we since found a more efficient way?) and is there an easy way to remove the little chrome control knobs without breaking everything?? Thanks everybody

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Turbo4whl

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Well the little cable slide and blower knobs are plastic push on type. The slide lever ends have serrations that grab the plastic. If they don't break (old plastic) when you pull them off, a little epoxy glue will remont them.

New heater hose holes, probably through the patch panel, or next to it. New holes for the air box studs also.

New hole for the blower air in also.
 
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Powerhouse Ranch

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Well the little cable slide and blower knobs are plastic push on type. The slide lever ends have serrations that grab the plastic. If they don't break (old plastic) when you pull them off, a little epoxy glue will remont them.

New heater hose holes, probably through the patch panel, or next to it. New holes for the air box studs also.

New hole for the blower air in also.

where is this hole for the blower air in? thanks
 

Turbo4whl

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where is this hole for the blower air in? thanks

Borrowed this picture from Casey's post. The hole will be next to where your current evaporator air goes in.

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You can also see where the 3 heater box studs go through the firewall. The fan box air hole is not as large as the evaporator hole, but almost as big. See the blower resister, right behind it.
 

Turbo4whl

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This should be where you need one of the bolt holes for the heater box:

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Another heater box mounting hole will be in your patch panel with the new heater core holes. Another hole straight down from the red arrow hole.
 

Powerhouse Ranch

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This should be where you need one of the bolt holes for the heater box:

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Another heater box mounting hole will be in your patch panel with the new heater core holes. Another hole straight down from the red arrow hole.

This is all gold, i know exactly what you're saying. although, are you saying there's a patch panel with holes or at least outlines for the correct location of the new heater core?

thanks for the illustration, really helps things out
 

89Suburban

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I been through all of this AC delete stuff. But all the pics in my thread are gone. I'll look in my hard drive when I get a chance tomorrow and see if I saved any of them.
 

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89Suburban

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89Suburban

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Powerhouse Ranch

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In the non ac setup, there are two brackets that hold in the heater core right? In my assembly there is only one, and there are two screws where the second should be, yet it would be hard to get that bracket around the hose ports on the core? not sure if it's missing or not a thing in the first place
 

Powerhouse Ranch

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@89Suburban ,

Right now with this swap, one of my biggest hurdles is the heater core straps. The assembly i bought came with the bottom strap, but the top strap around the heater core inlets was missing, but the screws are there. Do you have any pictures of that bracket up close? So i can see better what i need to find or have to fabricate
 

89Suburban

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@89Suburban ,

Right now with this swap, one of my biggest hurdles is the heater core straps. The assembly i bought came with the bottom strap, but the top strap around the heater core inlets was missing, but the screws are there. Do you have any pictures of that bracket up close? So i can see better what i need to find or have to fabricate

I’ll take a look later today and let you know.
 

89Suburban

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@89Suburban ,

Right now with this swap, one of my biggest hurdles is the heater core straps. The assembly i bought came with the bottom strap, but the top strap around the heater core inlets was missing, but the screws are there. Do you have any pictures of that bracket up close? So i can see better what i need to find or have to fabricate


I could not find any pics but I DID find these if it helps!



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