AC Evap core leak? Pics (1 Viewer)

[Biga27110]

Hey guys, I've had a small slow leak for years, but now ac fails after 2 weeks. I took a peak into the evap box to see if I can see any dye glowing. Its hard to tell it seems as if dirt and mud also glow under uv light. I can't find a leak anywhere else; I know this is a common failure. Does it look like a primary suspect to you guys as well?

 

[fjc-man]

Any signs of the dye coming out of the evaporator housing drain hose?

 

[Biga27110]

Any signs of the dye coming out of the evaporator housing drain hose?

Nothing noticeable I havent used my AC for months. I was thinking of recharging and adding more dye but that costs almost as much as just getting a new evap core. Truck has 250k miles.

 

[ceylonfj40nut]

Get a refrigerant electronic nose from HF. It’s cheap. It will pin point leak. Done it on several rigs and shown leak area better than dye.

 

[Biga27110]

Get a refrigerant electronic nose from HF. It’s cheap. It will pin point leak. Done it on several rigs and shown leak area better than dye.

Thank you I will try this tomorrow as well.

 

[Biga27110]

I bought a sniffer its not really going off in the evap box and I cant pin point a leak anywhere. Hmmm. The mystery remains.

 

[2001LC]

Get a refrigerant electronic nose from HF. It’s cheap. It will pin point leak. Done it on several rigs and shown leak area better than dye.

I was wondering, if those cheap sniffers any good! THX

@Biga27110
Try sniffer around the compressor and all point in engine bay. Work your way back to rear AC in RH rear 1/4 of body. I had one I couldn't find with dye. Turned out to be small leak in compressor. Seems it would leak most during the winter, when cold. It's my understanding in CA, you must fix. Just topping, is not allowed by law.

 

[fjc-man]

Usually the telltale sign of the place it’s leaking, you see oily residue ( refrigerant oil ) where the freon is escaping.

 

[Biga27110]

I was wondering, if those cheap sniffers any good! THX

@Biga27110
Try sniffer around the compressor and all point in engine bay. Work your way back to rear AC in RH rear 1/4 of body. I had one I couldn't find with dye. Turned out to be small leak in compressor. Seems it would leak most during the winter, when cold. It's my understanding in CA, you must fix. Just topping, is not allowed by law.

Thanks will do.

Usually the telltale sign of the place it’s leaking, you see oily residue ( refrigerant oil ) where the freon is escaping.

I found a spot I will take pics but there is no dye and the sniffer doesnt pick anything up.

 

[shtbrwn86]

Usually the telltale sign of the place it’s leaking, you see oily residue ( refrigerant oil ) where the freon is escaping.

Mine was leaking from the HP line that runs along the radiator (probably damaged during radiator repair). I could visibly see the oil/dye with no UV light or goggles or anything. That leak looked pretty bad but the AC functioned just fine for a while like that. I replaced that line and now I am having to evacuate/rechard the system every 10 months or so, yet I can't see dye anywhere.

My question about the sniffers is will there be anything to sniff once the system has lost a certain amount of pressure? I'm picturing an O-ring under pressure letting some refrigerant out. As soon as the pressure gets low enough the o-ring seats again and system is sealed, if that makes sense. almost like a check valve. Or do these systems continue to leak enough to be detected?

I did get one of those harbor freight sniffers but haven't tried it yet. I will report back. The only places I didn't check for dye was the two evap cores and the lines coming into the rear AC.

 

[Biga27110]

Mine was leaking from the HP line that runs along the radiator (probably damaged during radiator repair). I could visibly see the oil/dye with no UV light or goggles or anything. That leak looked pretty bad but the AC functioned just fine for a while like that. I replaced that line and now I am having to evacuate/rechard the system every 10 months or so, yet I can't see dye anywhere.

My question about the sniffers is will there be anything to sniff once the system has lost a certain amount of pressure? I'm picturing an O-ring under pressure letting some refrigerant out. As soon as the pressure gets low enough the o-ring seats again and system is sealed, if that makes sense. almost like a check valve. Or do these systems continue to leak enough to be detected?

I did get one of those harbor freight sniffers but haven't tried it yet. I will report back. The only places I didn't check for dye was the two evap cores and the lines coming into the rear AC.

Awaiting your results. I'm getting the same effect I lose pressure. Every time I only need to fill a tiny amount to get it back to cooling. Very strange.

 

[shtbrwn86]

Okay, so I pulled the front evap cover. Don't see any obvious leaks, but I did pick up one of those Harbor Freight AC sniffers and still couldn't find anything. So today I went and had my system evacuated and recharged (no leaks found on vacuum) and they said they put 2lbs of refrigerant in there, so it was really low. They also put dye in it, but so did the last two places that recharged it. I can't for the life of me see how I could lose that much refrigerant since I last had it charged 10 months ago and I don't see a massive leak somewhere.

Anyway, back to the AC sniffer, does this sound like the leak is coming from the evap core? I have never used one of these, but it seems to spike pretty good in there.