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willinthe985
06-24-2009, 11:29 PM
Ok, yesterday I was leaving the house and I got three or four houses down the road when I heard a boom and saw what looked to be steam coming from under the hood. The truck was all ready warmed up from a 3 hour drive home so I thought the radiator or hose busted, but there was no fluid on the ground and no obvious leaks when i opened the hood. I'm thinking it was a a/c hose. I didn't check and see if it still blows cold air still yet. How else can I check to see if there's any refrigerant still in the system or where find where the hose would be leaking?

Thanks guys.

Oldiron2
06-24-2009, 11:37 PM
What year vehicle? Any idea which refrigerant? R134a?
Was the AC on at the time? I wouldn't expect particularly high pressure in the system, if not.
If a major leak did occur, the refrigerant would have carried some lubricant with it which should be visible on the nearby parts unless everything was already an oily mess.
It might have leaked from a failed overpressure valve, or from a good one if an internal obstruction caused an overpressure condition.

willinthe985
06-24-2009, 11:46 PM
96' gmc sierra. I think it's 134a, I got the pump replaced last year so it has whatever the new required stuff is. Yes the a/c was on.

denrep
06-24-2009, 11:55 PM
...I heard a boom and saw what looked to be steam coming from under the hood....

What was someone saying about mixing propane and butane for a refrigerant substitute? :blob2:

Oldiron2
06-25-2009, 12:03 AM
If the system is low or empty, a pressure switch should keep the clutch from turning on. Might it still be under warranty? If they didn't clean the system out well, it may have plugged up the orifice, assuming that system uses one.
Aside from checking the things mentioned, if you don't know about or have the needed equipment, it's probably best to take it in for work.

willinthe985
06-25-2009, 04:54 PM
If the system is low or empty, a pressure switch should keep the clutch from turning on. Might it still be under warranty? If they didn't clean the system out well, it may have plugged up the orifice, assuming that system uses one.
Aside from checking the things mentioned, if you don't know about or have the needed equipment, it's probably best to take it in for work.

The system plugging up makes sense because the a/c seemed like it hasn't been working well the past few weeks.

6010
06-26-2009, 10:17 AM
Oldiron2 gave you some good advice. If you heard a boom and it was the AC there will be oil, and it will let you know where it is leaking. You will need to have a vacuum pulled on the system to remove the moisture after he leak is repaired, and you will probably need more oil if a lot was lost.

One thing about the 134A gas that everybody might not know. It is heavier than air, and odorless. For this reason any big commercial units, just about all of them being sold these days, if they are enclosed in a room must have a continuous monitoring system to alarm when a certain level of gas is detected. The pick up lines are placed strategically where the chillers are most apt to develop a leak. The 134A, being heavier that air, can fill a persons lungs and cause him to suffocate before he knows what is happening. We installed ours so that along with an alarm it would cut on exhaust fans as well. as extra protection we also installed controls that before entering the room a person could cut on the exhaust fans and they would stay on for 30 min. The operators usually spent on 5 minutes in the room each shift when they made their rounds. This kept the moisture down in the room also. I worked in a paper mill and the 134A was just one of the many things that could get you if you weren't careful.

It was easy to get people to switch over to the 134A. They just made the R-22 more expensive per pound than platinum. :)

The picture is a picture on me at my retirement party from the paper mill. They said they couldn't recognize me unless I had on the clothes I normally wear so they made this for me.

willinthe985
06-26-2009, 03:47 PM
Well, my stepdad's going to bring it in where it got worked on last summer to see if it's under warranty still. Is the oil died like a blueish-purplely(technical talk right there) color?

6010
06-26-2009, 08:08 PM
A lot of times the gas has dye in it so you can find the leak and it looks like you found it. I hope it is a hose or fitting that is easy to change.

willinthe985
06-30-2009, 05:05 PM
well, went go get it fixed today. The clutch was broken, keeping it engaged all the time. The sound i heard and vapor i saw was the overload valve doing it's job. It did have a warranty, only bad news is that it expired less than 2 weeks ago. So a new clutch, evac, new refrigerant, and labor was $430. :(

duaneb55
07-21-2009, 04:33 AM
*forgot i was on dad's (duaneb55) laptop until i posted . . . opps! lol*

hate to bring up an old thread and I apologize for the hijacking in advance, but your troubles reminded me of my recent a/c troubles. Dad and I just got my '83 s10 blazer back on the road (after being out of comission for about 5 years) Well we had an a/c pump on it so I could drive it but it didn't have the right connection type so it was just 245 a/c for awhile (sometimes 270 or even 280 :laugh: ) Finally got around to renting the a/c clutch removal/install tool kit from o'reilly's (piece of junk, the tips mushroomed out) only to find out that the good clutch on the newer compressor has a shorter "snout" which wasn't apparent until we had both compressors pulled apart. Luckily my "temporary" vehicle was a '90 s15 jimmy that became somewhat of a parts vehicle for the blazer, but we were hoping to leave the a/c system unopened incase we decided to sell it. Well we got the donor compressor in place, pulled a vac on the system (and it held), and chargered up the system. Well everything was nice and cold for a couple days until i went to start it up and i heard a loud "pop" and all the refrigerant came "steaming" out from under the hood (and into the cab since the vent seal is shot). I opened the hood and the connection on the back of the compressor had blown off . . . I felt like such an idiot since i was the one that tightened it down and should have realized that something felt funny when the threads were stripping. Oh well lesson learned. After another trip to o'reilly's for the proper helicoil (dad was all out) and another $40 in 134a we fixed it up, and went through the charging process again.

Certainly not as costly as your fix, but still a pain.

Oh yeah, and it's pretty unmistakeable when the system empties into your engine bay . . . tons of vapor and everything is coated in an oil.