Spring has sprung in Idaho.. So has the temperature here it going up into the 70-80*F mark.

Well, I truned on the A/C for the first time this here and it was very weak at best... So When I got home I got out the trusty A/C pressure guage and checked it.

Engine Running at Idle... MAX A/C fan on HIGH. The pressure starts at 25-30 and sinked until it hits about 5 PSI and the compressor shuts down. (Low pressure cut off)

So I when to WalMart and grabbed 2 cans of 134A Freon 13 Oz cans. (11 Oz of Freon and 2 Oz of PAG Oil with RED dye)

I return home again and hooked up the guage again the same way and started with first can... The pressure still the same...

Added second can... The pressure now is up to 25-30 PSI and steady. The compressor is running continuously. I shutdown and called it a day...

Got up this morning to go to church no problems... Finished at church and fired up the truck and turn on the DEF/FLOOR with middle heat. The compressor starts grunting hard! I turn off everything. Can't find anything wrong and drove home.

Now I figure I'm going to wash the truck and the glass is hot so I run the DEF with the TEMP set to COOL. Compressor starts GRUNTING again! But this time I see it spraying out oil! Then shuts off... I notice the oil coming out of a orfice in the back of the compressor. (Pop off valve???)

I hook up the guage again and check to find that the pressure is up to 35 PSI still not to high but... GRUNTING HARD....

So I release so of the freon and the GRUNTING stopped... Now the compressor cycling and the air isn't as cold but the pressure is at 25 PSI...

My question is what happen here? What is wrong with is picture?

 

I am not sure about the blowing of oil, but it sounds like you overcharged it with two cans. You might even need to clean out the condenser (the coil in front of the radiator). If you do clean it, be careful since the fins bend fairly easily.
Tom
I wish spring would come here. We have had snow for the last week.

 

The condenser was washed out good and got rid of the dead bugs...

It a small orfice in the back of the A/C pump and it squirt out a small quantity of oil... As for overcharging it wouldn't the pressure be high?

 

I think that is a hi overpressure blow off valve. When you charge up an a/c system useing guages, you need to monitor the low AND HI pressures. You watched the low pressure, but what was the hi side? If you charge it on a cool day, you have to keep the hi pressures a bit lower because when it gets hot out, the hi will go up significantly. The pressures will vary depending on the outside air temp, humidity, how much cooling the evaporator is doing, and eng rpm's. The best and safest way to charge up an a/c system is start out by evacuating the system completely and charge it up according to weight. monitor your hi and low guages to make sure they are in the correct range and it is done.

 

Ok...

Hemicat, I got one of those Malmart specials thats got the guage on the hose. Just screw on a can of freon and go...

I've got no way to check the high side since the nipple is different from the low side. Not only that but I don't think that cheap WalMart gauge will hanlde the high if it could...

I guess I'm going to find a local shop to evacuate the system and start over...

Currently I got about 25 PSI and the pump is cycling on/off... No grunting... I guess for the time being it ok... What do you think???

I'm more used to the R-12 system with a sight glass. You filled it until the bubbles were gone and the lowside pressure was about 40-50 PSI... But that old school...

 

Also, when you checking the pressure, it's a good idea to bump up the idle to about 2000 rpms as well as place a large fan in front of the condensor on high. You would be supprised to see what the pressures do when you take these two steps.

 

You are absolutely right on that!!! It is too hard to fill the A/C system by guage pressures only. So many things will change the pressure with a given amount of refrigerent. An experienced tech can fill a system close to correct by guage pressure because he knows the things that change pressures and compensates for them while reading the guage, but he always has to use a hi and low guage.
If your low is 25 now, and cycling without noise, it may be close to correct BUT in Idaho it is still COLD (by southern NM standards) and that will reduce the pressures. You will have to recheck it on a HOT day, and you should get a set of guages to check both sides of the system. or just let someone recycle yours and charge it up according to weight.

 

Well once I again I learn something new from all the guys here on the site...

I going to talk to another buddy I've got in town and see if he can do this for me... Recycle the 134a and reload by weight...

I let you guys know what's up...

 

You can find these for around 50 bucks. If you have a tool guy in town (snap on, mac, matco) they often have used sets when techs upgrade. I bought a used set a long time ago for around $40. I hardly use them anymore at work as our equipment takes care of everything. They are nice to have around the house though.