a/c installation in older caddies

[judgepauls]

Is there anyone who specializes in installing oem a/c's in vintage caddies? I 'd like to use original vents and controls, but will go with a modern Sanden compressor. I'm especially interested in '61 and 62's. Will ship the vehicle to the right guy.

[jwwseville60]

Judge

#1

Any good restoration shop with Caddy experience can help you, but it's an oddessey. Call CPR to start.

I have a 1963 FW sedan that has a new Sanden compressor and condenser that is high pressure R134. A newer kit of some kind (?) added by the clueless former owner. It doesnt work well at all in the daytime humid heat and barely at night. Yes, yes, it's in full working order, no leaks. (46-48 deg. only at the vents).
The only new components added that I can see were the compressor, hoses, fittings and condenser. I fear thats the issue, the mixing of old components and new. A cheap, lazy-man's fix.

Some folks have good luck with new aftermarket AC kits but not me, not when it's a hybrid system using the factory evaporator, dryer, dash vents and vacuum operated doors.

The original GM system was for low pressure R12 gas. I will be retrofitting a standard 1963 GM compressor and go back to R12 with this car. Factory everything. Be advised our beloved Caddies had primitive insulation, firewall protection and (fading now) window tints. R12 was and is very COLD.

My personal experience advice using the factory dash vents and doors is... to add a MODERN evaporator, hoses, dryer, expansion valve and condenser with the new compressor. You will probably have better results IMHO.

#2

On my Caddy wagon I have 2 custom systems that are R134, dash and a rear mounted unit. We are struggling with that as well (42 deg at the vents). We are now overdriving the engine fan and removing a trans cooler from the new HD condenser. If that fails to produce 28-32 degrees at the vents I will go with a second 7-vane compressor. Hells-bells, if I have to bolt on an RV AC unit on the roof I will !

Electric fans may help or may not. You will have to experiment. The engine fan has a lot of air sucking power. A 5 blade one is necessary.

Hope this helps. It's my usual long answer to a short question!

[Big Fins]

I've never heard of any automotive A/C system putting out 28^o-32^o at the vents other than an old 70 Chrysler that I used to have. On that we moved the sensor bulb off of the evaporator outlet tube just a little.

On my '76 the only thing we changed was the compressor, hoses, condenser to a parallel flow unit and used a VIR kit on it. Also blocking the heater return line with a ball valve got me another 8^o colder temperature at the vents. It will do 39^o-40^o in the heat of the summer that way.

[Eric DeVirgilis CLC# 8621]

The original A/C in a '59 I had was so cold, frost actually formed on the outlets.

[Big Fins]

The original A/C in a '59 I had was so cold, frost actually formed on the outlets.

That was an entirely mechanical system, capable of being manually adjusted to do that. Today's versions are someones idea of what you are supposed to like.

I want my car as cold as I can get it in the Florida summers. Introducing hot water into the system because some sensor dictates it's too cold, is BS. The aftermarket system from Old Air Products I had in the '59 would turn the evaporator into a block of ice if I set it that way. It would be totally useless as air flow was nonexistent. But, back the thermostatic control off just a hair and you could hang meat in that car.

[Moody]

Original vent usage is just an issue of piping to them. Controls are a different story in aftermarket air. It can be done. But why not find an original system and install that with R12? R12 is still available from Air Liquide, and others.

["Cadillac Kid" Greg Surfas 15364]

If you do get 30 degree air out of the vents that would mean you have an evaporator temperature of 27-28 degrees. The moisture in air will freeze at 32 degrees of course so that means the coil will soon ice up stopping air flow. While the coil is icing and the air flow is reducing, evaporator temperature will decrease so for that short period of time you have sub cooled air. Not a sustainable condition.
Proper supply air temperature to avoid drafts and ensured mixing of the supply air with cabin air is something on the order of 20-22 degrees below the preferred cabin temperature. With a desired cabin temp of 72 degrees the supply air should be on the order of 50 degrees. That is what you will see in just about all commercial and residential AC systems
Greg Surfas

[judgepauls]

Thank you all. Being new to the Forum, I posted this inquiry a second time because I couldnt find this one.

[jwwseville60]

Block of dry ice, a caffeinated squirrel on a treadmill and an old electric fan will do the trick in the end. Stop wasting money folks.