1977 280z AC -- issue # xx of yy

[ess1]

Forgot to mention the spec of the elbow, B-F6500-06-06 BRASS 3/8" MALE FLARE x 3/8" FEMALE FLARE. 90 DEGREE FITTING, got it from rnlhydraulics on ebay.

[240zadmire]

I think I found  the leak, hopefully the only place.  It is actually the schrader valve on the low input.  It leak so slow that I overlooked last time I did the soap test.

Instead of soap water, I just fill the valve with water and patiently wait for more than 5 minutes with laser eye fixated on the valve.  The leak is about one tiny bubble about the toothpick per 5 or so minutes.   I recheck it every 5 minutes or so and there it was, another bubble.  How do you go about fixing this with the refrigerant still full?  I put a cap with the o-ring in it already and hopefully good enough for now.

 

regards

 

[240zadmire]

this might be the solution for me, for now

https://www.autozone.com/cooling-heating-and-climate-control/a-c-service-valve-cap/p/dorman-a-c-service-valve-cap-902-025/825033_0_0?cmpid=LIA:US:EN:AD:NL:1000000:GEN:8062087320&gclid=EAIaIQobChMI_oeZ9LfG-AIViT-tBh1ULAfREAQYAiABEgLcqvD_BwE&gclsrc=aw.ds

 

[SteveJ]

27 minutes ago, 240zadmire said:

I think I found  the leak, hopefully the only place.  It is actually the schrader valve on the low input.  It leak so slow that I overlooked last time I did the soap test.

Instead of soap water, I just fill the valve with water and patiently wait for more than 5 minutes with laser eye fixated on the valve.  The leak is about one tiny bubble about the toothpick per 5 or so minutes.   I recheck it every 5 minutes or so and there it was, another bubble.  How do you go about fixing this with the refrigerant still full?  I put a cap with the o-ring in it already and hopefully good enough for now.

 

regards

 

I thought it didn't exist, but I just searched. It exists! This allows schrader valve replacement without losing charge.

https://www.amazon.com/MASTERCOOL-81490-R134a-Remover-Installer/dp/B000KITSMI

Of course, this is for 134A service ports. I'm not sure if one exists for R12.

Edited June 24, 2022 by SteveJ

[240zadmire]

Well, it was good for couple of months.  Found 2 other leaks.  One is on the back side of the compressor.  This will need a big o-ring and disassemble the compressor to fix.  The other is at the condenser.  Must have been a giant bee with a steel stinger that poked a hole.  
 

have anyone try the Red Angel A/C seal?  What about using MAP gas to blaze the leak at the condenser?

 

regards

 

[Captain Obvious]

I know practically nothing about A/C, but I have two thoughts:

First is about the leak seal... I don't know any mechanic ever who has even remotely liked any of the sealing additives in anything. Tires, radiator, A/C. Anything. Ever. In fact, my local pro says he won't even evacuate a system if he's told that it has some sort of leak stop in it. Won't put his machine on it.

Second thought is about brazing the leak in the condenser. Again, I'm no expert, but there's no way I would try that while the system had refrigerant in it. The pressure will just blow the braze material away from the hole, and even more importantly, you absolutely do not want to light anything fluorocarbon on fire. Bad idea.

[240zadmire]

I’m more inclined to do the brazing.  But who knows, some one on this forum might have a very good result with sealing too.

I need to do more research, by research, I mean watch more YouTube, to learn how to braze.  Of course it will be off the car or at lease zero pressure before I do it.

 

[Dave WM]

I would second not using a sealer, but I have no experience with it either. IIRC its alum so maybe one of the alum braze rods would be the ticket.

[Zed Head]

 

[HusseinHolland]

On 9/15/2022 at 11:45 PM, 240zadmire said:

I’m more inclined to do the brazing.  But who knows, some one on this forum might have a very good result with sealing too.

I need to do more research, by research, I mean watch more YouTube, to learn how to braze.  Of course it will be off the car or at lease zero pressure before I do it.

 

There's no way you will successfully braze an aluminum tube in an AC condenser. The age of the material and the thickness will just create additional holes. Just buy a new condenser.