Archived AC leak, can't find it!!!!

[Jakebud]

Have had my truck to the dealer about 5 times this year for a persistent, but so far impossible to find freon leak in the system. The freon has been bleeding out over the course of about five weeks as of late. The Dealer has used a bunch of die and the sniffer and can never find a thing when it is in the shop. They even pulled out the dash last week to check the evaporator and associated lines. Any ideas?



Thanks,



SPIKE

 

[Bschneider]

God only knows, I'm afraid. Could be so many things in so many places. There's only two things I can suggest:



1) Find another dealer.

2) Find a specialty AC shop, pay them to find the leak, and have Dodge fix it. If you're up front with the AC guy, he shouldn't mind being the one who finds it.

 

[Andy Redmond]

Ck. the low pressure switch (and sealing oring its located on the accumalator/dryer) and around the compressor clutch shaft seal.



Operate a/c, shut off vehicle, remove blower resister and stuff the sniffer up in the evap cavity, often this will assist you finding a prob. with an early evap leak.



If they removed the dash and the blower box, and the evap was leaking they should have immediately noticed the a/c oil and dye on the evap core.



Other than that maybe a seal/o-ring intermittantly leaking when stress is applied to the leak area (rough road shaking a/c line etc).



If the compressor was building too much pressure and "popping" off, you would think they would have noted abnormal pressures when the manifold guages were attached (too high on the red/hi psi/discharge/liquid side).



Evap core failure is common! Often the complaint starts as yours; then the recharge will last three days, then one day, then a steady leak that you can hear hissing in extreme situations.



Good luck

Andy

 

[JCrank]

What kind of dye are they using ? The red dye ? The new flourescent dye that is available is wonderful for leak detection. If the system is operational (charged up), then you can run the a/c for several days under a variety of conditions, and then you use a blacklight to look for the leaks. The dye will glow a bright flourescent lime green under the blacklight. My best buddy who is a fleet mechanic uses the flourescent dye and blacklight method and reports it works even better than using a "sniffer".

 

[Jakebud]

JC



The folks at my local dealer have been using the fluorescent stuff/black light in addition to the sniffer. Five weeks ago, they put in dye and charged the system. Two weeks later, I brought it in for a check, and it was still full. Three weeks after that, it was empty yet again. This is getting a bit frustrating!



SPIKE

 

[DLove]

compressor front seal, or maybe the schrader valve (the quick disconnects that they hook the gauges to). It could also be a chaffed line that is not quite cut all the way through, in that case there would be little or no oil leaking hence no dye. Small a/c leaks can be very hard to find, I know I've chased some for hours. Another method is to recover the system and pressurize it with dry nitrogen, then you go over it with soapy water. Hopefully they're not billing you for the lost refrigerant since this is a come back. If they're wasting your money/ time I'd consider going elsewhere, but it really can be this hard to find a leak.

 

[Jakebud]

I can't complain about what my dealer has charged me so far in looking for my leak. They haven't charged me a cent for any of the visits this year. I really appreciate that. Lithia Dodge in Omaha. Used to be Jim's Dodge.



SPIKE

 

[Stamey]

It took a year to find it for sure, but I found my evaporator leaking with the flourescent dye. Last year the system was fine until June, just as I was leaving for Muncie. I threw a quick charge on it, so I wouldn't be late to meet my caravan, and took the gauges and R134 with me to Muncie so I could charge as needed. The darn thing didn't leak a lick from that point until this June. I had put the flourescent stuff in there last year and could not find anythign. This year I charged it again, and put more dye in there. The next day it had leaked down, so I pulled out the black light and crawled around under it, after charging and running it again. I could see no place where the dye was showing, until I noticed the water dripping from the evaporator to the ground glowed like cooling water at Three Mile Island.

The evaporator and heater core have been replaced.



Chris