How do I find a/c leaks?

[texadelphia]

Any tips on tracking down refrigerant leaks in the ac system? I have some dye in the system and have looked at the compressor, lines in the engine bay, and the drain in the firewall and can't find any dye besides what spattered when I took the fitting off after filling with refigerant/dye. There may have been a few droplets on the casing of the compressor but it was really faint and hard to tell.

I'm assuming a leak in the evaporator would show up at the drain. Otherwise it seems like the only way to check the evaporator and expansion block is to pull it out from under the dash which requires pulling the refrigerant out of the system and disconnecting the lines in the engine bay.

Is there anything I'm not thinking of? Any way to do this without dropping cash on an electronic leak detector or tearing everything apart?

 

[nissanh]

Did you recenetly remove any of those connectors?

The leak could be at the fill port. Apply some soapy water and see whether it bubbles.

Toyota has their AC's good for life. My corolla is approaching 30 years and still got all factory AC and blows ICE cold air in west TX weather: Yes I clean the condenser. 1997 4Runner and 2000 LC AC has never been touched!

 

[gamefreakgc]

A can of refrigerant after you return the can is what, $10? How much refrigerant are you losing and how fast? Does it leak only when the A/C runs in the summer?

My point to these questions is it may be simpler and cheaper just to recharge the system several times a year than to fix it.

 

[brillo_76]

Well I cant about all environmental conditions, in the salt belt... Condensers only last about 15 years max.. The aluminum starts to oxidize and deteriorate the fins start to rot out etc..

So mostly the condenser, dryer along with the pumps need replaced.

The dye injection will pinpoints the leaks. With the age of these rigs. Its not common for these components to need replaced. Basic wear and tear.

 

[Konkordmusk]

Any tips on tracking down refrigerant leaks in the ac system? I have some dye in the system and have looked at the compressor, lines in the engine bay, and the drain in the firewall and can't find any dye besides what spattered when I took the fitting off after filling with refigerant/dye. There may have been a few droplets on the casing of the compressor but it was really faint and hard to tell.

Refrigerant dye is generally UV sensitive. A black light, and a dark area work wonders.

 

[texadelphia]

This rig has spent it's whole live in the PNW so corrosion isn't really an issue. There's hardly a spot of rust on it.

Point taken about just topping it off. Thing is I just topped it off a couple days ago and checked it yesterday under similar conditions and it seems like it's dropped pressure by about 10 psi. However, the pressure seems to fluctuate a bit each time the compressor kicks on. Could just be the cheap gauge but sometimes it dropped to about 15psi and other times it was up around 25 psi. The low reading just made me think that maybe it's losing refrigerant at a rate that's going to require topping it off every couple weeks. It could be that when I filled it I just didn't put enough in though. We're going to be moving to Texas in a couple months and I was just trying to be proactive in case I need to get it repaired.

I'm just going to sit on it for a while to see if it does drop to nothing again, but I was just curious about the best way to check for leaks in the meantime. It doesn't seem to be leaking anywhere in the engine bay though.

BTW, I have been checking for leaks with a black light/yellow goggle set.

 

[texadelphia]

Did you recenetly remove any of those connectors?

The leak could be at the fill port. Apply some soapy water and see whether it bubbles.

Toyota has their AC's good for life. My corolla is approaching 30 years and still got all factory AC and blows ICE cold air in west TX weather: Yes I clean the condenser. 1997 4Runner and 2000 LC AC has never been touched!

I didn't remove any connectors. Just filled at the lower pressure port. Maybe I'll check to see if that's leaking.

That's funny you say that about your Corolla. I have a '91 that uses R12 that developed a leak 12 years ago. Spent $1000 for a shop to unsuccessfully try to fix it. I ended up just taking the compressor belt off and going without rather than converting it to R134a.

 

[brillo_76]

If your sure you don't have any leaks and everything is in good working order.

You can always have it sucked out and pressured down test.
If it can hold a vacuum for a few hours then you don't have any leaks.
Make sure the correct amount of refrigerant goes back into the system.

If I were to do this.. I would replace at least replace the dryer as it keeps the refrigerant dry.

As I blew a compressor once, playing around with the just top it off method. As most independent shops with some size to them have a 134A recharge/ evacuation system that can pull your refrigerant out then vacuum test it down for a more thorough leak test.


Just a thought: Your condenser fins are clean of dirt and debris ?