1953 Cadillac 60-Special "The Muskogean Phoenix"

[kudims]

Air Conditioner: Factory vs. Dealer

A Rather Specific Topic — and possibly not all that interesting to the broader subset of my already narrow readership.

What's this about? Observed differences in factory vs. non-factory A/C installations for the 1953 model year.

According to the GM Build Sheet, my car spent a full week at the factory. Typically, a car would ship out to the customer no later than the day after its body and chassis reached the final assembly line. My guess is the Cadillac was held for off-line A/C installation. If that's correct, then the details of that process might have varied from one vehicle to another.





Below, using photos from various cars, we'll look at some differences between factory-installed air conditioners and those installed outside the factory (e.g., at a dealer or a specialized shop).

1. Air Intakes



Factory: All Fisher Body shells slated for A/C had those "ears" at the rear window line right from the start.



Here's how they looked.



Dealer: If A/C was installed at the customer's request at a dealership, no openings were cut into the body. Air intake was strictly recirculated cabin air. No switch between cabin/outside air intake.

2. Roof Vents and Ducting



Dealer: Cold air entered the cabin through vents on the rear package shelf—likely unpleasant for those hit by a blast of cold air to the back of the head. But routing lines to the overhead area wasn't part of the dealer's job. However, I saw several factory installed A/Cs for 1953 with no roof ducts... But in any case dealer would never make anything with the headliner...



Factory: Cold air travels up to the headliner via transparent ducts (this photo shows condensation on the duct). On the left is a switch to choose outside air or cabin recirculation.



Dealer: The headliner is the standard type with no ceiling vents.



Factory: There are four vents in the headliner, one above each door, providing cold airflow from overhead.



Factory: Nevertheless, some cars with "factory" A/C lacked the overhead ducts; cold air distribution was effectively the same as a dealer-installed system.

3. Under-Car Routing



Factory: There's a filter/dryer on the high-pressure line.



Dealer: The filter is relocated, and in its place is just a piece of tubing. The bracket holding the lines appears custom-made.

4. Control Unit



Dealer: The A/C control blocks for factory vs. non-factory installs are essentially the same.



Factory: Identical-style blocks were used through 1956.

5. Radiator "Mask," Horns, and Supports



No A/C: The horns are mounted low, attached to the radiator opening.



Dealer: The horns had to be relocated to fit the condenser.



Dealer: Horns are spaced out differently to accommodate the condenser.



Factory: Horns were positioned at the upper radiator bar - not to interfere with the condenser.



Dealer: To install the condenser, the vertical brace of the center support is cut. Someone even added (maybe much later) an auxiliary fan for the condenser.



Factory, No A/C: The central strip has a reinforcement rib.



Factory: The vertical support is trimmed slightly differently than the dealer's version, but for the same reason—to fit the condenser.

6. Different Compressor



Factory: Compressor model A1, with the high-pressure port at the rear face and the low-pressure port on the right side.



Dealer: Appears this car originally had a different, newer compressor. As a result, the lines for the ports differ completely from the A1. We can't rule out a later replacement compressor, but I suspect that if someone was adding A/C in, say, 1956–57 (or later), they wouldn't bother installing the huge, lower-efficiency 1953–54 compressor.



Dealer: Closer look at the port arrangement.



Dealer: The sight glass and filter/dryer are on the right fender splash shield.



Factory: No under-hood filter; it's located down on the frame. The sight glass and bypass solenoid are in the engine bay.

7. Carburetor with Load Compensation



Dealer: A Rochester carb with no built-in load compensator to boost idle speed under A/C load. That's another clue that this A/C was added off the assembly line. Next photo explains why.



Factory: A Carter carb with an electro-vacuum load compensation system. When the A/C is switched on, it energizes a vacuum-solenoid valve (mounted on the carb). Vacuum then pulls on a diaphragm, moving that linkage (pictured) to raise idle speed. In 1953–54, only Carter carbs had this feature, so every Cadillac with factory-installed A/C in those years came with a Carter carb.

Those are the main differences I've noticed.



VIN: 5360. The "53" stands for 1953, "60" for Series 60, then the production sequence number—80k+ out of roughly 100k total units. Likely, it had dealer-installed air conditioning, not from the earliest portion of the model run, so presumably not a factory job.

Thanks for reading! If anyone sees other telltale differences or has their own knowledge regarding these first-in-history automotive air-conditioning units and how they were installed, please share!

And, btw, I read 1950-53 Authenticity Manual, and I can notice several things that are not correct there, not only related to A/C 

[David King (kz78hy)]

Here is the link to the 53 data book.  On page 190 of the .pdf file (3 or 4 books combined into the file) it discusses the A/C option, function and content.

https://www.gm.com/content/dam/company/no_search/heritage-archive-docs/vehicle-information-kits/cadillac/1953_Cadillac_Eldorado_VVI.pdf

[kudims]

Here is the link to the 53 data book.  On page 190 of the .pdf file (3 or 4 books combined into the file) it discusses the A/C option, function and content.

https://www.gm.com/content/dam/company/no_search/heritage-archive-docs/vehicle-information-kits/cadillac/1953_Cadillac_Eldorado_VVI.pdf

Yes, I have this document, although I have another technical manual, which is 100% related to 1953 air conditioners.



One of the pages from 100+ page manual

[James Landi]

Installation of a/c looks very similar to my '56 model,and you've done incredibly wonderful work ... the ceiling vents are identical.  For those who have never experienced these systems, believe me, they are memorable.  Having frigid air blowing on the left side of your face as you drive and having condensate drip on your neck is memorable... additionally, on particularly hot, humid days, side windows  fog up. When I was using my '56 to commute 90 miles a day, I used a towel over my shoulder to keep dry and warm.  These systems had sufficient capacity to cool down a hot car in a very few minutes.   

[David King (kz78hy)]

The image in the "accessories" appears to show the same content as the assembly plant build.  At least routings and things like the dryer are shown.

[kudims]

Let me share some photos and statistics regarding the trip "Montana - Texas".
2200 miles in 4 days on a 1953 Cadillac. Who did the same or similar trip in recent time / past - please share memories and photos.



Day 1: Hamilton - Dubois through Yellowsone National Park



First "technical stop" for brief inspection after 60 miles from Hamilton. Somewhere in Wyoming.



In Yellowstone



We spent there several hours. Somewhere near Grand Geyser





But we had to drive and find a place to "stop for the night".



Traffic was really heavy





Snow in June





We went through the very heavy rain with hail high in the mountains, and now we are driving down the hill to Dubois...



Super 8 in Dubois. Nice place



Next morning



"Breakfast in America"

Day Summary: We covered 460 miles (740 km).
Here's the breakdown by refueling stops:

Start with a full tank — Odometer: 35580

35732: 10 gallons to full (always filled to the brim) — 15.2 MPG
35879: 13 gallons — 11.3 MPG (thin air and long climbs)
36040: 12.95 gallons — 12.4 MPG (same mountain terrain).

Daily Total: 460 miles at an average of 12.8 MPG.
Elevation gain: from 3000 ft in Montana to 8100 ft in Wyoming and up to 8450 ft in Yellowstone, followed by a descent to Dubois (6850 ft). Pretty result good considering high altitude and a 71 year-old carb.

[kudims]

[James Landi]

Entirely forgot about the "favorite stations" feature... so nice.  I wonder when the vacuum tube, two component tuner and audio amplifier/ power supply system gave way to a single integrated transistorize unit. 

[kudims]

Day 2: Dubois - Colorado Springs

On the second day we understood that the car can move pretty fast without issues. So, I tried to cruise at 60-65. This was the optimum speed in terms of fuel economy, and I was more or less confident that at this speed no hose will blow-up accidentally...



Day 2 map: 500 miles



Some beautiful views of Wyoming



... and Colorado



Brief stop at ACE store. Edsel Corsair 1959





Then we continue out trip



Colorado



Approaching Denver... There was a car accident and a very heavy traffic. Our Caddy had a bit late ignition, and was starting to heat-up in slow move with 90+ F outside. So, we stopped for 40 minutes until it became clear on the highway



Colorado Springs



Parked near the hotel

Day 2 statistics:

Odometer reading at start 36040
Refuelings:
36247 — 14.6 gal (14.2 MPG)
36440 — 14.12 gal (13.7 MPG)
36552 — 9.2 gal (12.17 MPG) (Colorado Springs)

Total day 2: 512 miles, average economy: 13.5 MPG