I've replaced-repaired, cleaned and tested the complete system so I'm confident that everything will work as new. I vacuum tested the system first to see first if the installed system had any leaks. The controls moved the trap doors and turned the fan on as stated in the Tim's AC manual. My issue is that after flushing all of the components that are required to be cleaned or replaced, the only thing left to flush or make sure that it is in good condition (no contaminants) is the compressor itself. It came from a system that was closed to the best of my knowledge but had no refrigerant in the system and had just a little oil in it, so I think it had a severe leak somewhere in the system. I can turn the compressor by hand and can feel the internal workings seem to be just fine, but I'd like to know what is required to make sure the compressor itself has no contaminants in it. 

At this point all I need to do is add the required oil and gas up the AC unit, but I'd hate to have to go through all of the work flushing the system and the cost of replacing the items required to make the system serviceable.

Has anyone dealt with this before?

Views: 64

Reply to This

Replies to This Discussion

the compressor has very little capacity to hold in contaminants other than in the crankcase, so that's where you should be focused. Assuming that you will be charging with R134a, the main problem is that the original mineral oil is not capable of dissolving in R134a (non miscible is the term), so all of the original oil must be removed to prevent liquid 'slugging' in the suction side.  You should drain the oil, filll it with solvent flush, drain it again, then fill it with ester oil (which sorta kinda mixes with mineral oil) turn the compressor by hand to mix, and drain that out.  then you should be able to refill it with oil and charge the system. 
After a small run, since it was open (a system with a leak is considered open once it's empty), then i'd empty and recharge the system to assure that all the mineral oil is gone.

if you have r12, simply change the oil and charge.  that oil is bullet proof.  just make sure you get mineral oil and not pag or ester. 

I do have r12 and mineral oil. Thanks for the response. I haven't found anything anywhere that helped me and I was hesitant to just bul into what ai thought would work.

I've had several cads of this vintage but many years in the past and never needed to do anything to the AC system. Prices are higher and too many aftermarket systems that are not only more expensive but don't get appreciately colder than the original unit. I'm in the northwest part of Washington so we don't get 100+ days of heat very often and when that happens, I just put my little boat i n the water and go have a beer in the Islands till it cools off a bit.

Thanks again for the help.

I got my AC back working too and gotta refill with R12… where did you find mineral oil? 

Rock auto



  • Add Photos
  • View All


Title and Frame VIN section for sale

Started by Russ Austin in General Discussion. Last reply by Russ Austin 23 minutes ago. 5 Replies

For sale is the #1 frame cross member that has the vehicle VIN on it. Comes with the matching Arizona title in my name.  This is legal in Arizona, please check your state laws before putting this on…Continue

Steering gear compatibility

Started by Matti Roth in 1963/64 Cadillac Specific Discussion. Last reply by Matti Roth 1 hour ago. 2 Replies

The steering gear in my 64 is leaking from steering shaft side and I need to rebuild it. I have used steering gear from 70`s Monte Carlo available. Is there any reason why not to use that temporarily…Continue

Current 1963/64 Cadillac Listings on eBay

Started by Jason Edge in 1963/64 Cadillac Specific Discussion. Last reply by Jason Edge 10 hours ago. 1 Reply

To see all 1963/64 Cadillacs Listed on eBay in the USA…Continue

Tags: ebay

Blog Posts

1964 power steering sector rebuild

Posted by CHRIS CARLSON on March 20, 2023 at 11:32pm 3 Comments

 I'm having my steering sector rebuilt, and considering changing it from 20-1 ratio 4.2 turns lock to lock to 3.5 turns lock to lock @ 16-1 ratio, If i change from a 3 1/4" box to a 3" box i could have a 14-1 Ratio steering response would be faster, shorter distance to turn the wheel to get a response,   has anyone done this? and how do you like it? thank you

1964 Daville dashboard clock

Posted by Willem Bol on March 13, 2023 at 11:33am 2 Comments


Can somebody help me finding a dashboard clock  for my 1964 Cadillac DeVille Convertible?

Thank you in advance,

Willem Bol

The Netherlands

Does anyone know where I can get the bushings for AC compressor mount on the 429?

Posted by Robert Schles on February 21, 2023 at 11:45am 2 Comments

I've looked at the usual rubber sources but couldn't find any. 

Need help with a hood latch

Posted by Curtis Dover on January 2, 2023 at 5:23pm 0 Comments

Hey guys, I need some help.  Could someone send me some pictures on how the first hood release lever on a factory 1964 Cadillac is set up, where it comes though the grille. Not the secondary one. I need to know where the thumb or finger position is located through the grille. Is it above or below the center grille molding piece? Mine seems to be positioned behind the center molding piece and will not adjust above or below the molding. I have a wire tied to it to release it…



  • Add Videos
  • View All

© 2023   Created by Jason Edge.   Powered by

Badges  |  Report an Issue  |  Terms of Service