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Discussion Starter #1
This has not been a good weekend! :-( I've been preparing for weeks to get the AC in my 66 coupe working and thought I had everything thought out. I'm no expert by any stretch of the imagination but I have worked on AC systems before (my 65 Tbird, 92 Olds Silhouette) and have done so successfully. I even bought an electronic leak detector to help me fine minor freon leaks (works great by the way).

Here's what happened today, if anyone has some thoughts as to what's happening I'd appreciate a reply.

Installed new condenser.
Installed new dryer.
Installed new AC belt.
Siphoned old oil from compressor, flushed with denatured alcohol.
Ran a vacuum on system for 45 minutes.
Installed 6 ounces of esther oil via funnel into compressor. The retrofit kit I purchased had three cans of combination 134/oil/stop leak which I assumed would give the system the correct amount of oil.
The retro kit has a hose with a gauge on it for the low side, and since I could not find a 134 fitting that fit the schrader valve on the high side I did not check the pressure there -- relying instead of the low side readings.

First can of refrigerant went in normally -- can slowly got cold and took about 10 - 15 minutes to empty. The Gauge however had me stumped. It started way high, like 65 psi and then dropped to near zero as the can was empty. I usually only monitor the high side when I've done AC work before so I didn't know if this was normal or not.

Added 2nd can, same phenomenon: pressure started off high, then dropped off to zero. Air inside the car was still hot, no sign of cooling. Added additional 1/2 can and go my leak detector out. Engine compartment area and condenser checked out, so I checked inside the car. Sure enough, I found a major leak (according to the detector)from one of the lines going into the evaporator. I thought I had it pretty snug when I installed it but I could clearly see oil and bubbles, even heard a hiss now that I knew where to look. Got out a wrench and tightened it as much as I could and the hissing stopped. The leak detector stopped showing a major leak but still chirped a little, but this could have been because of residual refrigerant in the area.

Started filling the system again, pressure on low side was near zero when I started. Still baffled by this -- the leak inside the car didn't seem that bad. I grabbed my leak detector and was just getting inside the car when all of a sudden it sounded like a bomb went off. Holy [censored]! was all I could think. My poor dog just stood there staring at my car and a blown hose that was whipping about like a rabbid snake. And of course everything within 10 feet got covered in R134 and oil! :-(

Turns out the high pressure line from the compressor (the one going to the condensor) blew right off it's connector at the compressor. It will be no big deal to replace it, but I really think something is going on I don't understand and have never encountered before.

Any suggestions before I go into round two with this beast? I was sooooo counting on taking the Stang out on my next date and having the AC working.

Thanks in advance for any help you can give! :)
 

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Sounds as if it's pumping the refrigerant from one side of the system to the other . It can only do that if there is a clog in the system . If say the condensor has something plugging it the freon can not flow . Other good question to ask you is if the interior ever started to cool ? Did it blow any cool air during the filling ? Id recheck the connections by taking the hoses off everything and make sure something is not plugging a inlet . I had a A/C system I worked on 2 days after someone else in the shop installed a new hose , compressor , expansion valve , and a few other small parts . Guy brought it back because it stopped cooling and blew off the over-pressure fitting . I put a little freon in to get it up and started troubleshooting it . Within a minute or so I could tell there was a plug in the condensor . I pulled the same hose off that blew on yours and there was a large chunk of rubber that was stuck in the condensor . Turns out the new hose had a loose piece of rubber inside it from when the end was crimped on . It shot out and right into the condensor inlet , almost completely plugging the systems flow . That resulted in it trying to pump 4.5 LBS of freon into a 4 foot long hose ...... which does not work out too well .
 

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Discussion Starter #3
Interesting...

Here's one thing I noticed and was stumped -- then promptly ingnored it thinking my logic was wrong. After siphoning the old oil out of the compressor I tried to blow oil out of the hoses by blowing compressed air into the line that goes to the evaporator. To my dismay, the air filled it up like a baloon -- it did not pass through the system and out the other end as I thought it should. Like I said, I scratched my head and thought maybe it wasn't supposed to be free flowing. My experience in this stuff is quite limited to what I've encountered before.

Should the air have blown through the hose? If so, I guess that would mean the blockage is in either the hoses going to or from, or in, the evaporator itself. Is there a way to isolate this before tearing the unit out? As hard as it was to stop the leak in that one line in the back of the evaporator I'd hate to take it off.

By the way, no, the system never to start blowing cool air. I had a thermometer in the vent and it was always at or near 90 degrees.

Now, the fact that the line was leaking at the evaporator, does that help me narrow down where the blockage might be -- if that's what's going on?

Thanks again for your help!

:)
 

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I am sure there are plenty experts here, but just wanted to share another forum from a shop here in Phoenix, these guys are the a/c guru's of America ::

AMA AIR
 

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Discussion Starter #5
Thanks, HandyMan -- just posted same question there. Hope someone can help...I'm frustrated.

By the way, love the picture of your son behind the wheel. :)
 
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