Red Assembly Mark on A/C boxes - The 1947 - Present Chevrolet & GMC Truck Message Board Network

**IronCanine** · 01-05-2020, 02:43 AM

On some A/C boxes there was a red paint mark from the factory. At least I interpret it as paint. I have seen many more boxes without a mark than ones with a mark. I believe it to be a Harrison mark, not a final assembly plant mark. But I am speculating. It appears on other GM makes of the era and on vehicles from different assembly plants. The location of the mark can vary. Most all I have seen were at the top front, but I have seen it at the bottom and side. Here are a few pics I've collected from the board at large and from members directly. First two pics are St. Louis trucks, fifth pic is Flint. The fourth pic is from our build and an attempt to recreate this mark. I have had conversations with members about the meaning of this mark and found no consensus. I didn't have much luck noodling around the Corvette, Chevelle or Camaro forums either. F.A.A.Benny would be a good voice to offer an informed perspective on this.

I'm not aware of other threads discussing this and thought a discussion and pics might be of use to someone down the road (and I have an affinity for factory processes/markings). If nothing else maybe we can get another thread with factory underhood A/C pics.

BigBird05 · 01-05-2020, 09:24 AM

That mark is usually a quality control mark.

**IronCanine** · 01-05-2020, 09:34 AM

Quote:

Originally Posted by BigBird05

That mark is usually a quality control mark.

That was my assumption due to the limited frequency.

**DeadheadNM** · 01-05-2020, 10:39 AM

Good thread. Here are some Flint assembled 72 K5s w red dot.

**maverickmk** · 01-05-2020, 10:56 AM

I am no AC expert, but I wonder if it is either the high side or the heat/exit side - ?

davischevy · 03-23-2020, 09:23 PM

That is new one for me. I'll probably spend all morning tomorrow out back doing "Research".

**IronCanine** · 03-23-2020, 09:47 PM

That'd be great Larry. Pics if you can.

davischevy · 03-23-2020, 10:21 PM

Quote:

Originally Posted by IronCanine

That'd be great Larry. Pics if you can.

I have a half dozen original paint Chevelles too. I will look them over too.

72swbcamo · 03-24-2020, 01:49 PM

I have two A/C units and half of a housing where the mark would be. One has the red mark, not a nice round circle, more like the red mark in the last picture in the thread. I have no idea what it means but it sure is a great conversation starter. I'm sure someone on this site will come up with the definitive answer.

**FirstOwner69** · 03-30-2020, 08:32 PM

This is on a '72 currently on Phoenix Craigslist. Looks like a Janesville truck.
https://phoenix.craigslist.org/evl/c...092213597.html

**IronCanine** · 03-30-2020, 09:42 PM

Great addition Jim. Best one I've seen.

**402Bowtie** · 03-20-2021, 11:52 PM

Barely in the pic, but there. This is a Baltimore truck. https://denver.craigslist.org/cto/d/...294467795.html

**IronCanine** · 03-21-2021, 12:01 AM

That's a nice truck and a bright mark. Thanks for the addition.

01-05-2020, 02:43 AM	#1
IronCanine I'm trying.... Join Date: Oct 2013 Location: Athens, GA Posts: 2,759	Red Assembly Mark on A/C boxes On some A/C boxes there was a red paint mark from the factory. At least I interpret it as paint. I have seen many more boxes without a mark than ones with a mark. I believe it to be a Harrison mark, not a final assembly plant mark. But I am speculating. It appears on other GM makes of the era and on vehicles from different assembly plants. The location of the mark can vary. Most all I have seen were at the top front, but I have seen it at the bottom and side. Here are a few pics I've collected from the board at large and from members directly. First two pics are St. Louis trucks, fifth pic is Flint. The fourth pic is from our build and an attempt to recreate this mark. I have had conversations with members about the meaning of this mark and found no consensus. I didn't have much luck noodling around the Corvette, Chevelle or Camaro forums either. F.A.A.Benny would be a good voice to offer an informed perspective on this. I'm not aware of other threads discussing this and thought a discussion and pics might be of use to someone down the road (and I have an affinity for factory processes/markings). If nothing else maybe we can get another thread with factory underhood A/C pics. Attached Images __________________ 1970 K20 Z62 https://67-72chevytrucks.com/vboard/...56#post9334756 1970 Blazer http://67-72chevytrucks.com/vboard/s...d.php?t=645076 1969 K10 SWB CST http://67-72chevytrucks.com/vboard/s...52#post8520352 1971 K20 Z84 https://67-72chevytrucks.com/vboard/...90#post9047290 1946 B.F. Avery Model A Tractor http://67-72chevytrucks.com/vboard/s...55#post8292555 "Sometimes I wonder if zander208 was even real..."

01-05-2020, 09:24 AM	#2
BigBird05 Registered User Join Date: Aug 2019 Location: Cheraw Posts: 1,300	Re: Red Assembly Mark on A/C boxes That mark is usually a quality control mark.

01-05-2020, 10:39 AM	#4
DeadheadNM Carpe manana Join Date: Dec 2010 Location: Eau Claire, WI Posts: 12,449	Re: Red Assembly Mark on A/C boxes Good thread. Here are some Flint assembled 72 K5s w red dot. Attached Images __________________ 1972 K5 CST Highlander Blazer: http://67-72chevytrucks.com/vboard/s...d.php?t=708547 1972 K20 Cheyenne Super: http://67-72chevytrucks.com/vboard/s...d.php?t=528308 Members met: ORANGBLAZ, 2003 silverado, MikeCofield, BB72CHEVKT, Duncan&Son, Sameyrasmea72, THENEWMEXICAN, HotRod C/10, brianthelion02, Sport/Truck, ryanroo, michael bustamante, Dirt's72, Already Gone, WestButteTruck, 57taskforce, Moreyel, painterljp, AASmedic, SoCoC10, Lumaestas, carbuff382, Chevyland

01-05-2020, 10:56 AM	#5
maverickmk Senior Member Join Date: Nov 2019 Location: Cocoa FL Posts: 596	Re: Red Assembly Mark on A/C boxes I am no AC expert, but I wonder if it is either the high side or the heat/exit side - ? __________________ Die with memories, not dreams. Not to brag, but I don't need alcohol to make really bad decisions. 1969 GMC Short Step Side

03-23-2020, 09:23 PM	#6
davischevy Registered User Join Date: Sep 2008 Location: Harrison, Arkansas Posts: 9,863	Re: Red Assembly Mark on A/C boxes That is new one for me. I'll probably spend all morning tomorrow out back doing "Research".

03-23-2020, 09:47 PM	#7
IronCanine I'm trying.... Join Date: Oct 2013 Location: Athens, GA Posts: 2,759	Re: Red Assembly Mark on A/C boxes That'd be great Larry. Pics if you can. __________________ 1970 K20 Z62 https://67-72chevytrucks.com/vboard/...56#post9334756 1970 Blazer http://67-72chevytrucks.com/vboard/s...d.php?t=645076 1969 K10 SWB CST http://67-72chevytrucks.com/vboard/s...52#post8520352 1971 K20 Z84 https://67-72chevytrucks.com/vboard/...90#post9047290 1946 B.F. Avery Model A Tractor http://67-72chevytrucks.com/vboard/s...55#post8292555 "Sometimes I wonder if zander208 was even real..."

03-24-2020, 01:49 PM	#9
72swbcamo Active Member Join Date: Dec 2003 Location: Waterbury, CT Posts: 591	Re: Red Assembly Mark on A/C boxes I have two A/C units and half of a housing where the mark would be. One has the red mark, not a nice round circle, more like the red mark in the last picture in the thread. I have no idea what it means but it sure is a great conversation starter. I'm sure someone on this site will come up with the definitive answer.

03-30-2020, 08:32 PM	#10
FirstOwner69 Senior Member Join Date: May 2010 Location: Wisconsin & Arizona Posts: 4,852	Re: Red Assembly Mark on A/C boxes This is on a '72 currently on Phoenix Craigslist. Looks like a Janesville truck. https://phoenix.craigslist.org/evl/c...092213597.html Attached Images __________________ Jim

03-30-2020, 09:42 PM	#11
IronCanine I'm trying.... Join Date: Oct 2013 Location: Athens, GA Posts: 2,759	Re: Red Assembly Mark on A/C boxes Great addition Jim. Best one I've seen. __________________ 1970 K20 Z62 https://67-72chevytrucks.com/vboard/...56#post9334756 1970 Blazer http://67-72chevytrucks.com/vboard/s...d.php?t=645076 1969 K10 SWB CST http://67-72chevytrucks.com/vboard/s...52#post8520352 1971 K20 Z84 https://67-72chevytrucks.com/vboard/...90#post9047290 1946 B.F. Avery Model A Tractor http://67-72chevytrucks.com/vboard/s...55#post8292555 "Sometimes I wonder if zander208 was even real..." Last edited by IronCanine; 03-20-2021 at 11:56 PM.

03-20-2021, 11:52 PM	#12
402Bowtie Registered User Join Date: Sep 2003 Location: Wichita, KS Posts: 3,735	Re: Red Assembly Mark on A/C boxes Barely in the pic, but there. This is a Baltimore truck. https://denver.craigslist.org/cto/d/...294467795.html Attached Images __________________ Link to Parts I am Selling Build Date Thread: GMC, 68-71 Chevy, 72 Chevy

03-21-2021, 12:01 AM	#13
IronCanine I'm trying.... Join Date: Oct 2013 Location: Athens, GA Posts: 2,759	Re: Red Assembly Mark on A/C boxes That's a nice truck and a bright mark. Thanks for the addition. __________________ 1970 K20 Z62 https://67-72chevytrucks.com/vboard/...56#post9334756 1970 Blazer http://67-72chevytrucks.com/vboard/s...d.php?t=645076 1969 K10 SWB CST http://67-72chevytrucks.com/vboard/s...52#post8520352 1971 K20 Z84 https://67-72chevytrucks.com/vboard/...90#post9047290 1946 B.F. Avery Model A Tractor http://67-72chevytrucks.com/vboard/s...55#post8292555 "Sometimes I wonder if zander208 was even real..."



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