Help with air conditioner leak! Its 100F out there!

[98EdBomber]

Had the ac "fixed" a few years ago. I know they replaced the dryer but im not sure what else was replaced(lost receipt). Its worked fine since this summer. Just went hot all of a sudden about 2 months ago.

Thought Id run through the simple things first before i spend any money on gauges, dyes, etc and thought you guys might have a stab at what it possibly could be.


So...

Checked all fuses/relays(which i dont think there is a relay on my model...just 2 fuses) related and all are good.

Seems like there is still pressure on the low side. I press the valve for a half second and a hiss was heard.

Compressor kicks on and then off again right away. Blower blows great...just hot as you know what.

When i noticed the air getting warmer 2 months ago i added a diy can of R134 and then about 2 weeks later it got hot again. If I had a leak of any sort I think by now the system would be empty and i wouldnt have any pressure on the low side. Just an idea.

I know the ac system is complex but i am familiar with all of the components so I was wondering if anyone might have any great ideas on how to get this solved. My next step is to buy gauges and a vacuum and refill it with accuracy. Then perhaps go to the dye, but if theres no leaking, then Im stumped as to what could be the bad component and how to narrow it down.

Im getting tired of 4- 60 air!!!

Please help!

Thanks
TJ

 

[dustybumpers]

You need to put a can of dye in, it's available same place you got the can of 134 you put in.
Run the system for at least an hour, then park close to the house, so you can strech a electric cord to it

When it gets dark, take a black light, and check all under the hood with it. Where ever your leak is, will glow green under the black light.

Check your low pressure switch by the dryer, it's probably leaking. I just replaced mine. While you have it off, there is an o-ring that needs replaced where you took off the switch. Make sure to use the same size GREEN one like you remove. They sell a A/C o-rings where you bought the 134. Use pag oil to lube the seal, or it will tear, and you will have another leak

 

[koda2000]

i think you definitely have a leak somewhere and the only way you're gonna find where is with the dye and the black light or by taking it to an a/c shop. it could be a pressure switch, an o-ring, the compressor seal or even the condenser. it's less likely to be a hose, the evaporator or the drier/accumulator, but not impossible. i'd find the leak before i'd spend money on gauges or a vacuum pump. once you've found and corrected the problem, throw in some refrigerant and see if the problem is solved.

 

[98EdBomber]

i think you definitely have a leak somewhere and the only way you're gonna find where is with the dye and the black light or by taking it to an a/c shop. it could be a pressure switch, an o-ring, the compressor seal or even the condenser. it's less likely to be a hose, the evaporator or the drier/accumulator, but not impossible. i'd find the leak before i'd spend money on gauges or a vacuum pump. once you've found and corrected the problem, throw in some refrigerant and see if the problem is solved.

If there was indeed a leak somewhere, then how am i still getting air to HISS out from the low side valve? Now granted I havent taken an actual psi reading yet with a gauge but there seems to be a substantial amount of pressure still in the system by the sound of the hiss when I push the needle down on the valve.

 

[budwich]

IF you are adding r134, you got a leak... the stuff just doesn't disappear into the system. Its that simple. As for why there is pressure, get a gage and find out how much. IF it is less than the low pressure switch "trigger", you have your answer. IF it isn't then you have to do more extensive testing. The fact that you compressor is rapid cycling is the "standard sign" of poor fill levels.

 

[98EdBomber]

IF it is less than the low pressure switch "trigger"


Care to elaborate on this? I catch on quick but Im not sure what you mean by trigger and what that psi should be. I think normal ranges are around 42 iirc on low side when at normal operation.

And that leads to my next point. Im guessing I will need to find out what the proper psi range is when refilled. Any ideas where this info is listed? All I have is the Haynes and finding a service manual for this model year is near impossible. I think its 42-49psi but i may be way off.

 

[koda2000]

in your original post you stated that the a/c system is complex. it's really pretty simple. you're finding that you need to add refrigerant, you compressor is cycling quickly and it's not getting cold. those are classic indications of too little refrigerant. as far as there being some pressure still in the system, that just indicates it hasn't all leaked out yet. even a flat tire still has some air in it. one area to check that i forgot to mention in my original post are the shrader valves (particulary the LO side) are a common place to leak. did you reinstall the cover last time you added refrig and is it's seal in good shape?

without using the dye there really isn't any more advise anyone can give you.

 

[98EdBomber]

in your original post you stated that the a/c system is complex. it's really pretty simple. you're finding that you need to add refrigerant, you compressor is cycling quickly and it's not getting cold. those are classic indications of too little refrigerant. as far as there being some pressure still in the system, that just indicates it hasn't all leaked out yet. even a flat tire still has some air in it. one area to check that i forgot to mention in my original post are the shrader valves (particulary the LO side) are a common place to leak. did you reinstall the cover last time you added refrig and is it's seal in good shape?

without using the dye there really isn't any more advise anyone can give you

LO valve cover is missing. Doesnt appear to be oily residue there but i did notice on the drier fitting( 3/4" maybe) that there was a little oily residue. Perhaps there is an o ring in that connection that has failed.

I guess I will have to end up getting a set of gauges and go from there. Thanks for the help. I will update my findings asap.

 

[koda2000]

LO valve cover is missing. Doesnt appear to be oily residue there but i did notice on the drier fitting( 3/4" maybe) that there was a little oily residue. Perhaps there is an o ring in that connection that has failed.

I guess I will have to end up getting a set of gauges and go from there. Thanks for the help. I will update my findings asap.

you can get a new valve covers from the auto parts store. the fact that you didn't see any oil on the valve means nothing nor does the slight amount of oil on the drier fitting, as the o-ring should have been lubed with PAG oil when it was installed. i honestly don't understand why you insist starting by acquiring a set of gauges. it's pretty obvious what their going to tell you and keep in mind the ambient temperature when testing makes a difference on pressure readings. you asked for advise, but you don't seem to be willing to take it. good luck!

 

[dustybumpers]

The pag oil doesn't seem to leave an oil residue like the mineral oil that went in with the 12. It's best to put dye in, My low pressure switch was leaking through itself, and out through the wiring harness. I was replacing seals, vacuuming the system down, and charging it back up every week. Wasted a lot of money, and time that way. Once I put the dye in, found it right away

 

[98EdBomber]

The pag oil doesn't seem to leave an oil residue like the mineral oil that went in with the 12. It's best to put dye in, My low pressure switch was leaking through itself, and out through the wiring harness. I was replacing seals, vacuuming the system down, and charging it back up every week. Wasted a lot of money, and time that way. Once I put the dye in, found it right away[/QUOTE

Im gonna fix it even it it means I dye trying

 

[dustybumpers]

Im gonna fix it even it it means I dye trying

Hahahahaha, good play on words... Good luck.