dodgethis Posted March 22, 2012 Report Share Posted March 22, 2012 Guys its about that time again with the weather ramping back up with the heat. I know i asked last before but I am just now getting the courage to think this through before I start getting my hands dirty on it. My A/C system is already filled, but when the compressor runs, i do not recieve any cold air when it runs. The compressor doesn't act up or whine, or cycle on or off repeatedly. My thoughts are is that due to the system is fully charged, there may be a blockage somewhere in they system. My bets would be to replace the Orifice tube, and then vacuum down the system and then refill it with refrigerant. The only question I am wondering is, if the system is already filled and one is going to remove the orifice tube, i would need to purge the refrigerant out of the system (no duh!), but is the orifice tube on the High side, or Low side? And if despite whichever side is best, i have no problem purging the low side however, what am i looking as far as the high side? I know the high side will but under more pressue, and will have liquid ready to gush out. I can't think of anything better but a rag, and a glove while doing it, (No Pun inteded ) yea, its a on a 98 Lumina 3100, with R134a Quote Link to comment Share on other sites More sharing options...
dodgethis Posted March 22, 2012 Author Report Share Posted March 22, 2012 Come on nobody? Ok, Ok I promise i will enviromentally safe while doing this Quote Link to comment Share on other sites More sharing options...
Schurkey Posted March 22, 2012 Report Share Posted March 22, 2012 Stop guessing, put gauges on it. Perform REAL diagnosis before you screw it up completely. This could be any of several potential problems, perhaps most likely the air doors under the dash aren't working properly. Might have NOTHING to do with the refrigeration system. It's pretty clear that you don't have a working knowledge of how A/C systems function. Might be best to have an experienced helper, because I don't see anything but heartache if you dive in alone in order to throw parts at it. Quote Link to comment Share on other sites More sharing options...
dodgethis Posted March 22, 2012 Author Report Share Posted March 22, 2012 Schurkey, I'm not guessing, I know what the pressures are, I do have a manifold gauge, and am well aware of how many people do not believe in the fix it in a can with a gauge. I would highly doubt my "air doors" have nothing to do with it, as i can cycle the air vents to different levels ie. legs, mid body, etc. Regardless, the system does not work, so my thought process is that the system may have a blockage, and the orifice tube is my belief for the cause of it. It would be a different story if i knew i was low on 134a, based on the reading from the manifold gauge, which i know im not. Quote Link to comment Share on other sites More sharing options...
Schurkey Posted March 22, 2012 Report Share Posted March 22, 2012 Schurkey, I'm not guessing, I know what the pressures are, I do have a manifold gauge, and am well aware of how many people do not believe in the fix it in a can with a gauge. I would highly doubt my "air doors" have nothing to do with it, as i can cycle the air vents to different levels ie. legs, mid body, etc. Regardless, the system does not work, so my thought process is that the system may have a blockage, and the orifice tube is my belief for the cause of it. It would be a different story if i knew i was low on 134a, based on the reading from the manifold gauge, which i know im not. If your high-side pressures are normal, it's not a blocked orifice tube. Blocked tube would result in high high-side, and low low-side pressure. The air doors that change from heater to vent to defrost, is separate from the door that would adjust temperature. Again, you need an on-site mentor. Quote Link to comment Share on other sites More sharing options...
Galaxie500XL Posted March 22, 2012 Report Share Posted March 22, 2012 X2...if the system was blocked, you'd be seeing very high pressures on the high side, and unsusally low pressures on the low side. So, what pressures are you seeing? I'd be particularly interested in seeing what the high/low pressures are when you first start the compressor, and what they are once the system has stabilized after running for a few minutes. Additionally, are you noticing any coolness or condensation at all on the exterior of the low side hoses? If your high-side pressures are normal, it's not a blocked orifice tube. Blocked tube would result in high high-side, and low low-side pressure. The air doors that change from heater to vent to defrost, is separate from the door that would adjust temperature. Again, you need an on-site mentor. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted March 22, 2012 Report Share Posted March 22, 2012 the temperature mix door runs solely off of an electric motor, which you can hear move around if your engine is off when going from full cold to full hot and back. the doors that control the direction of the air run off of a combination of vacuum and solenoids. to test the temp mixer, get the engine up to full temp, put the selector to blow out the dash vents, then go to full heat, see if it does blow heat and how long it takes. then move the selector to full cold(not a/c, just the temp dial), see how long it takes for the heat to go away. it should drop down to roughly ambient temps after ~10-15 seconds or so from the last time i did this. Quote Link to comment Share on other sites More sharing options...
dodgethis Posted March 22, 2012 Author Report Share Posted March 22, 2012 Again, you need an on-site mentor. Yes, Yes i do Schurkey, But then again if had one, i wouldn't be talking to all of you I'll go back and take pressure readings once i get off from work, and report back what I get. Robert, i'll give that a shot, and also report what i find. Quote Link to comment Share on other sites More sharing options...
alec_b Posted March 23, 2012 Report Share Posted March 23, 2012 I'm wondering is your compressor is even any good. Just cause it spins and is quiet doesn't mean it's any good. With the A/C on, look for 35-40 PSI on low side and ~200 PSI on the high side. The low side needle should be bouncing just a bit to show that the compressor is "pumping". Quote Link to comment Share on other sites More sharing options...
dodgethis Posted May 3, 2012 Author Report Share Posted May 3, 2012 Guys, sorry its been a while since i reported back. I just finished school and now have the time to look further into it. I just realized yesterday, that when I brought her into the garage that the compressor didn't even cycle on it once I had turned on the A/C. I havne't checked if I have blown a fuse, or have very low pressures on High and Low side. I will report back where i stand.... Quote Link to comment Share on other sites More sharing options...
ptcfast2 Posted May 3, 2012 Report Share Posted May 3, 2012 Keep us posted! I redid the entire HVAC system (minus the cores under the dash - I hope I NEVER have to touch those...the blood rushing to my head while under there makes me dizzy as heck!) on my 98 last fall, not the same issues per-say, but my compressor was wony as heck. Quote Link to comment Share on other sites More sharing options...
dodgethis Posted May 5, 2012 Author Report Share Posted May 5, 2012 Ok, Just got the time to hook up gauges to it. I found out that after jumping off the compressor, i see 10 PSI on the low side, and 25 PSI on the high side respectively. It looks like I need to find the leak..... Quote Link to comment Share on other sites More sharing options...
jman093 Posted May 6, 2012 Report Share Posted May 6, 2012 Ok, Just got the time to hook up gauges to it. I found out that after jumping off the compressor, i see 10 PSI on the low side, and 25 PSI on the high side respectively. It looks like I need to find the leak..... That's what I figured it probably was. I didn't want to say anything since you seemed certain it was full. 95% of the time, if the compressor is running, but the system won't cool, it's low. The compressor is probably your leak. It was pretty common on 3100's. When they leak it's usually visible from the compressor oil that has leaked out. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted May 6, 2012 Report Share Posted May 6, 2012 It was pretty common on 3100's. especially if you(or someone else) overcharges the system. i'm guilty of that one. A/C was working fine on the MC, thought maybe i'll add more refrigerant to get it colder. nope. start adding some, got a 1/2 to 3/4 can in and i start hearing a hissing noise... Quote Link to comment Share on other sites More sharing options...
dodgethis Posted May 6, 2012 Author Report Share Posted May 6, 2012 Totally understand, So should i just grab a can with dye and put it in, and see where the leak is? I hate to keep jumping off the compressor when it could be low on oil, and inadvertently destroy it. Quote Link to comment Share on other sites More sharing options...
RobertISaar Posted May 6, 2012 Report Share Posted May 6, 2012 it's POSSIBLE.... that you might find the leak without adding anything else.... i mean, its's leaking, and the oil that is in the system is going somewhere. if you have a fairly clean engine bay, you could probably find the leak location by following all of the A/C lines and looking for the bound to happen oil patch. the refrigerant i used, some leaked out of the can, oil included, looked kind of like a pale yellow. Quote Link to comment Share on other sites More sharing options...
yorxs Posted May 8, 2012 Report Share Posted May 8, 2012 I've owned half a dozen cars that had factory A/C failures and it is always the result, a leaking compressor. I've tried the dye tactic, its difficult to find the leak because the dye get blown all over everything. Now I just buy reman compressors on eBay for $75 and call it good. I currently own 2 cars that will be entering their 5th summer with eBay compressors. Bottom line, its a pretty good bet its the compressor, and you can cheaply replace it, oil it, vacuum it and charge it in under 2 hours. Quote Link to comment Share on other sites More sharing options...
xtremerevolution Posted May 8, 2012 Report Share Posted May 8, 2012 I have a good, working 3100 compressor that I will let go for CHEAP. I need it out of here before I send it to the junkyard. Quote Link to comment Share on other sites More sharing options...
dodgethis Posted May 8, 2012 Author Report Share Posted May 8, 2012 Well i'll give you guys an update, I have filled it back up with freon, and without putting any dye into the system I herd a hissing noise. Come to find out most of all the freon leaked out through the High side port. After I replaced the port, evacuated the system, and recharged she seems to be holding pressure. I hope due to the oringal low pressures that my oil didn't all flow out and it won't destroy the compressor. I'm figuring it didn't and just close the system off and let it ride. Quote Link to comment Share on other sites More sharing options...
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