AC Line Routing - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**lkt1954** · 05-10-2023, 11:03 AM

Working on the AC for my 70 C10 and I have a couple of questions on running ac/heater hose lines.

The firewall has been smoothed and an old air hurricane unit is installed. On this unit all the lines are on the right side and they are about 8-10 inches from the fresh air vent hole. It appears to me the only route I have is through the fresh air vent hole to run the lines.
My question(s) are- is there enough room where I have drawn the circle on the cab go through the firewall there (I can mock up the outer fender and run a tape line, as I would like to keep the line hidden) or can I run them out the bottom of the fresh air box and up the fender? I'm concerned there is not enough room in the front of the fresh air box to go that route ( its hard to gauge what room you have by just feeling that area.
I have both the diamond and vertical template for cutting the holes.
Any thoughts and/or suggestions here? I don't want to screw up a finished firewall.

Thanks

cornerstone · 05-10-2023, 10:24 PM

Jason VanNatta of VanNatta Fabrications sells a hose kit that does what you're looking for. The AC lines run through the inside of the fender between and above the wheel well and come out into the engine bay about where the original battery was mounted. Check out his videos on Youtube and his website to learn more. No Relation.

**lkt1954** · 05-10-2023, 11:38 PM

cornerstone- I have both style templates for the hoses, my concern is there enough room to place the as close to the outer edge where I have the circle drawn. Thanks for the tip.

HalfBrit · 05-11-2023, 12:35 PM

Hopefully these pics will help. Here’s the VanNatta Fab pass through and flange. Used the blower block off panel (part of the firewall smoothing kit) with the cutout, for a template. Just mocking mine up right now. Diving into the real metal work after I get a thousand other details finished.
Posted via Mobile Device

**lkt1954** · 05-11-2023, 04:52 PM

HalfBrit- thanks,thanks- that really helps.
Would it be possible for you to give me the measurements of how far over from the outside edge and up from the bottom you went.

Thanks Again
Larry

**lkt1954** · 05-11-2023, 11:23 PM

Also if anyone has a picture of the sheet metal removed in front of the fresh air vent and where the blower motor is, it would be interesting to see inside that cavity.

HalfBrit · 05-12-2023, 09:37 AM

LKT1954, I can't give you precise measurements. I'll try my best to describe it. The lowest area in the cutout is barely above the base of that fresh air cavity. Reaching through the interior (with the blend door off) you can feel where that is. Plus, looking underneath, you can see the firewall actually hangs down a little lower than the base. So that limits how far down you cut. The upper area runs into some of the hidden sections where the cowl and fresh air vent meet. And it's pretty close to the outer edge, as well. Probably to avoid getting into the areas previously mentioned. I'll post another pic of the fan block off patch panel, maybe giving you a better visual.

HalfBrit · 05-12-2023, 09:39 AM

Quote:

Originally Posted by HalfBrit

LKT1954, I can't give you precise measurements. I'll try my best to describe it. The lowest area in the cutout is barely above the base of that fresh air cavity. Reaching through the interior (with the blend door off) you can feel where that is. Plus, looking underneath, you can see the firewall actually hangs down a little lower than the base. So that limits how far down you cut. The upper area runs into some of the hidden sections where the cowl and fresh air vent meet. And it's pretty close to the outer edge, as well. Probably to avoid getting into the areas previously mentioned. I'll post another pic of the fan block off patch panel, maybe giving you a better visual.

Posted via Mobile Device

HalfBrit · 05-12-2023, 09:42 AM

Sorry for the double post.
One last thing. That cutout dimension may not be large enough for standard AC lines. I changed to EZ Clip hoses, which are smaller in diameter. It's a small area for all 4 lines.

**lkt1954** · 05-12-2023, 06:34 PM

Thanks

**lkt1954** · 05-13-2023, 07:00 PM

Finally pulled the trigger and got the connections mounted. I forgot there was a smaller fitting and cut out the same size hole as the rest. It will straighten up some when I put a cover plate over them. That's one advantage of these bring behind the fender- it's out of sight.
Thanks for all the pictures and help.

05-10-2023, 11:03 AM	#1
lkt1954 Active Member Join Date: Dec 2007 Location: Dumas, Texas Posts: 185	AC Line Routing Working on the AC for my 70 C10 and I have a couple of questions on running ac/heater hose lines. The firewall has been smoothed and an old air hurricane unit is installed. On this unit all the lines are on the right side and they are about 8-10 inches from the fresh air vent hole. It appears to me the only route I have is through the fresh air vent hole to run the lines. My question(s) are- is there enough room where I have drawn the circle on the cab go through the firewall there (I can mock up the outer fender and run a tape line, as I would like to keep the line hidden) or can I run them out the bottom of the fresh air box and up the fender? I'm concerned there is not enough room in the front of the fresh air box to go that route ( its hard to gauge what room you have by just feeling that area. I have both the diamond and vertical template for cutting the holes. Any thoughts and/or suggestions here? I don't want to screw up a finished firewall. Thanks Attached Images

05-10-2023, 10:24 PM	#2
cornerstone Registered User Join Date: Apr 2014 Location: Azle,Texas Posts: 2,248	Re: AC Line Routing Jason VanNatta of VanNatta Fabrications sells a hose kit that does what you're looking for. The AC lines run through the inside of the fender between and above the wheel well and come out into the engine bay about where the original battery was mounted. Check out his videos on Youtube and his website to learn more. No Relation. __________________ Brian 1972 C10, "Loyd", LWB to SWB, 5.3, L83/6L80e, 4:11 Tru Trac, Air Ride, VA, DD, 20" Coys, 4 wheel disc, A quick LS swap turned into a 6 year frame off resto-mod.

05-10-2023, 11:38 PM	#3
lkt1954 Active Member Join Date: Dec 2007 Location: Dumas, Texas Posts: 185	Re: AC Line Routing cornerstone- I have both style templates for the hoses, my concern is there enough room to place the as close to the outer edge where I have the circle drawn. Thanks for the tip.

05-11-2023, 12:35 PM	#4
HalfBrit Registered User Join Date: Feb 2021 Location: Kernersville, NC Posts: 84	Hopefully these pics will help. Here’s the VanNatta Fab pass through and flange. Used the blower block off panel (part of the firewall smoothing kit) with the cutout, for a template. Just mocking mine up right now. Diving into the real metal work after I get a thousand other details finished. Posted via Mobile Device Attached Images Last edited by HalfBrit; 05-11-2023 at 12:37 PM. Reason: Added text

05-11-2023, 04:52 PM	#5
lkt1954 Active Member Join Date: Dec 2007 Location: Dumas, Texas Posts: 185	Re: AC Line Routing HalfBrit- thanks,thanks- that really helps. Would it be possible for you to give me the measurements of how far over from the outside edge and up from the bottom you went. Thanks Again Larry

05-11-2023, 11:23 PM	#6
lkt1954 Active Member Join Date: Dec 2007 Location: Dumas, Texas Posts: 185	Re: AC Line Routing Also if anyone has a picture of the sheet metal removed in front of the fresh air vent and where the blower motor is, it would be interesting to see inside that cavity.

05-12-2023, 09:37 AM	#7
HalfBrit Registered User Join Date: Feb 2021 Location: Kernersville, NC Posts: 84	Re: AC Line Routing LKT1954, I can't give you precise measurements. I'll try my best to describe it. The lowest area in the cutout is barely above the base of that fresh air cavity. Reaching through the interior (with the blend door off) you can feel where that is. Plus, looking underneath, you can see the firewall actually hangs down a little lower than the base. So that limits how far down you cut. The upper area runs into some of the hidden sections where the cowl and fresh air vent meet. And it's pretty close to the outer edge, as well. Probably to avoid getting into the areas previously mentioned. I'll post another pic of the fan block off patch panel, maybe giving you a better visual.

05-12-2023, 09:42 AM	#9
HalfBrit Registered User Join Date: Feb 2021 Location: Kernersville, NC Posts: 84	Re: AC Line Routing Sorry for the double post. One last thing. That cutout dimension may not be large enough for standard AC lines. I changed to EZ Clip hoses, which are smaller in diameter. It's a small area for all 4 lines.

05-12-2023, 06:34 PM	#10
lkt1954 Active Member Join Date: Dec 2007 Location: Dumas, Texas Posts: 185	Re: AC Line Routing Thanks

05-13-2023, 07:00 PM	#11
lkt1954 Active Member Join Date: Dec 2007 Location: Dumas, Texas Posts: 185	Re: AC Line Routing Finally pulled the trigger and got the connections mounted. I forgot there was a smaller fitting and cut out the same size hole as the rest. It will straighten up some when I put a cover plate over them. That's one advantage of these bring behind the fender- it's out of sight. Thanks for all the pictures and help. Attached Images



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