Oooh boy. I remember you mentioning you weren’t getting cold air in la Canada .

I had this problem in my 82 240d. I recharged the system every other year till the leak got worse. Then I started looking for it. I finally found it by buying the halon gas detector from Harbor Freight. I snooped the entire system and guess where I found R134 spewing out? The center vents. Evaporator. I stuck the little sensor hose right down the center vents and it started squealing off the charts.

I tried leakstop but it had gone too far. It was no longer a slow leak. It would leak out in a few days. Rather than pull the dash I got rid of the car. A foolish move in retrospect but I had life constraints at the time and it was the path of least resistance.

Autozone free too rental is awesome. The pump and manifold I show in my AC rebuild threads is a loaner from there. I’ve borrowed it multiple times. I seem to get the same one every time.

I returned the halon gas tester to HF tools. They dinged me 20% but I figured that was the rental. I was really sad I had to let the 240d go. Had circumstances been different I’d have kept and fixed it.

__________________
79 300TD “Old Smokey” AKA “The Mistake” (SOLD)
82 240D stick shift 335k miles (SOLD)
82 300SD 300k miles
85 300D Turbodiesel 170k miles
97 C280 147k miles

This just happened to me too...

I had the system recharged last summer which carried me until a week ago.

I have to call the shop that did the work, but I suspect they used a UV dye as part of the service. I'm considering purchasing a black light to find the leak myself.
If not, is a halon detector the way to go? Though I suspect this doesn't detect residual gas (if that's even a thing) but live leaks only.

Assuming it was UV dye and the leak is something simple like a schrader valve, I'm half tempted to borrow the loaner AC pressure gauges from Autozone and refill the system with Envirocool or whatever it is people are using in lieu of 134a.

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1981 240D 4sp manual. Ivory White.

A Halon leak detector, now we're getting somewhere .

I'm still up to my eyebrows trying to get the 1979 Dodge D200 ready for Death Valley, it looks like I'll have to make my own smoke machine to find the evaporative leak, who knew a 2 quart glass jar with metal lid would be so hard to find ? .

Anywho, I will keep after this as 100 degree days in February is normal for California so I must needs address this .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better

The halon detector will detect residual gas. It is just a simple gas analyzer. People have mixed results depending on the flow rate of the leak and how much of an ambient breeze is blowing. It’s kind of a combination of how much fresh air you’re ventilating with and how much Freon you’re pumping out. Too much breeze and not enough leak = no signal. Too much leak and no breeze = signal but no hope of isolating the leak point.

It was pretty clear I had an evaporator leak when I stuck the probe down the center vent and it went nuts. In front of the dash it had some counts but the breeze coming in the windows was carrying it away. Once inside the vent duct the deeper I went the more the siren went off. It’s like a Geiger counter for Freon.

It may be smart to charge up the system with a little gas right before snooping if the system is totally empty. I put in a can of R134 and then started looking. The leak was so bad it would lose it in a week.

Good luck.

I really abused my 240d’s ac when I owned that car. I “converted” it with this Interdynamics kit from Walmart that was basically a bunch of fittings, some oil and a can of 134A. I started empty and didn’t evacuate the system. First I swapped out the seized compressor. Then I used a simple hose and piercer valve without a manifold. I pumped until I got cold air. Really ignorant. I suspect there was a enough water in the system that it eventually formed acid and ate through my evaporator after ten years.

When I rebuilt my 300D AC recently I vacuumed it for a couple of hours using the Autozone free rental pump and manifold. I wanted it dry.

Good luck finding those leaks. Hope it’s just an o-ring or cracked hose.

__________________
79 300TD “Old Smokey” AKA “The Mistake” (SOLD)
82 240D stick shift 335k miles (SOLD)
82 300SD 300k miles
85 300D Turbodiesel 170k miles
97 C280 147k miles

Yes, that is my hope too.....

Appreciate the help .

__________________
-Nate
1982 240D 408,XXX miles
Ignorance is the mother of suspicion and fear is the father

I did then what I knew how to do ~ now that I know better I do better