Possible Cures For R12 A/C Problems

[TED DIMON]

The A/C system on my '69 wouldn't keep a charge after I acquired the car last June.  So I put that problem on the back burner until I sorted out some other issues in the following months.
This February, I started cruising on EBay to see if there was any snake oil available that might help the problem.  I found a couple of items that seem to be working for me and I would like
to share them with you.

The first item is "R12 Superseal Repair metal rubber and stop leak kit for $29.75 including shipping.

The second item is Maxi-Frig R12 compatible AC recharge refrigerant in 6 oz cans.

George, my gray haired mechanic, checked the lubricant level, drew a vacuum on the system and then added one can of the Superseal and two cans of the Maxi-Frig to the system.
He continuously  ran the A/C in the car to thoroughly distribute the Superseal.  The air coming out of the vents in the cabin has been ice cold ever since....much colder than when he first 
charged the system with the regular R12  last summer.  I am now getting a nice 40 degrees at the vents and the leak(s) have been stopped.

Now I'm looking forward to driving the car this summer.  It does get hot here in Phoenix!

[Kennie B.]

When the system was leaking, did you bother to find the leak?  The product you used is only a stop gap solution.  Also, the R12 substitute you used is propane...think about that for a minute.

 I am in the midst of getting my system back in operation after the engine swap.  I had replaced all the hoses, has the condenser and evaporator checked for leaks and replaced the seal on the pump.  System was perfect except for the seal.  My solution was to take a spare pump to a rebuilder and this week is the unenviable job of swapping the pumps.  And yes, I will be using R12.  More efficient than R134A without the hazard of propane.

[TED DIMON]

Could not find any signs of a leak, apparently because it was so slow.
I was not aware that MaxiFrig is propane.  No problems so far and the
charge is holding because of the R12 Superseal that was used.  

[Ron Dame]

Propane is an excellent refrigerant, we used lots of it in ultra-low temp freezers. Yeah, there's the flamability issue, but if you still have some R12, it's not an issue anymore, as  that is a decent (though toxic) extinguisher.

[Kennie B.]

Ron, R12 isn't toxic but has been accused of damaging the ozone layer.

https://www.brighthubengineering.com/hvac/63281-refrigerant-r12-properties-advantages-and-disadvantages/

Frankly, the accusation has never been fully proved.  The position was 20 or years ago that the ozone layer was going to take many decades to possibly recover.  After only 2, it has made a huge recovery.  I'd say there is more happening than the intellectual elite can actually understand.

Ken

[TED DIMON]

On 4/27/2018 at 4:45 PM, Ron Dame said:

Propane is an excellent refrigerant, we used lots of it in ultra-low temp freezers. Yeah, there's the flamability issue, but if you still have some R12, it's not an issue anymore, as  that is a decent (though toxic) extinguisher.

Are you recommending that I add a small amount of R12 to the 100% propane that is in the system to act as an extinguisher?