A/C Recharge/Refill problem

[KillerKeller_jr]

Yesterday I decided to finish fixing my A/C, I replaced the Accumulator as the last step before attempting to refill the system. I know I should probably have the system flushed and vaccuumed since I replaced the compressor but wanted to test it for leaks before taking it in the a professional for that final task. My problem is when attempting to add just enough freon to test for leaks, what I think is the lowside, doesn't seem to be the lowside according the the gauge. Since the refill hose and connector I have states its only suppose to fit the lowside, not sure what is wrong here. Can someone shed some light on this...Where is the lowside A/C connector on a 95? Mine according to the fittings is the one closest to the firewall. If this is wrong then maybe I need to change the fitting out? I thought my mechanic would have stated that or fixed it last summer when I had the A/C flushed and filled shorly before the compressor went out. Any assistance or input much appreciated, let me know if you need pictures of what I am talking about.

[KillerKeller_jr]

I might have answered my own question...looked in my GM service manual and I am using the correct port (lowside). Only problem is I can't seem to get it to take the freon very well and the gauge goes nuts!! I have read several DIY sites on performing your own A/C maintenance, they state it is not neccessary to flush and vac the system but recommended. Apparently the Aurora has a replacement service tube now that will take the debris out of the system, but my compressor hadn't completely died, I thing the bearing was the only thing going out, cold air still worked but with alot of noise. So I think if I follow some other directions as follows I should be just fine unless someone here knows different.

1. Put the first can in upside down
2. Put the 2nd can rightside up
3. Add PAG oil to system
4. Test for leaks
5. Fill the system full with 3rd can

Hopefully that works and I don't blow up the system cause the gauge that I have sure acts funny, goes nuts, when I add freon to the sytem. Let me know your guy's opinions.

One more thing, why and how can the highside & lowside ports be on the same line? That is the way they are according the the service manual unless I am missing something?

Thanks

[KillerKeller_jr]

This forum use to be great back in the day....I could get answers in no time...now I just amuse myself....answering my own questions...where is everyone at these days?

Discovered my Freon Fill connector was bad, broken part. Bought a new one and was able to fill my sytem but I am unsure if I have enough freon, only added about 2 cans of freon. System has a sticker that states 2 lbs (32 oz) required, I only added about 26 oz plus 3 oz of Pag oil for a grand total of about 29 oz. Well I guess the important thing is I have cold air and was unable to find any leaks! I guess I will find out in a couple of days if I have any major leaks, hopefully none.

Next project is to replace my bald tires!!!

[zimaad]

you definately need to replace the orifice tube when doing this changeover. It's in the line between the high and low side fittings where there is a nut to disconnect the lines. Write down which way the part comes out so you get the new one in the right way. The part is cheap, less than $10. It's the thing and filters the crud out of the system. Also, this part is why/how the high and low sides are on the same line. It acts as a throttling valve to cause a pressure change in the system. The "other" pressure change in the system in the compressor itself.

Also, once you get the system all together, do not open it back up. The accumulator is a desicant system that basically sucks the moisture out of the closed system. If you allow moisture in it, you basically should get a new accumulator.

Wherever you go to refill/recharge the system should apply vacuum to the line. This is how the system is tested for leaks as well as remove any moisture in the system. They will put it under vacuum for a while(should be at least a half hour) to get out any moisture then close the valve to the vacuum pump and leave the negative pressure in the lines and make sure the pressure doesn't change after 15 mins or so. This will verify no leaks in the system. Adding a small amount of freon doesn't really do anything to test for leaks unless you have some sort of leak detection system like a sniffer or dye test kit. Not to mention, the system really won't work without proper amount of 134a. Those do it yourself low-pressure guage kits are ok to just top things off(in my opinion) but a high and low pressure manifold guage is much better to add refrigerant and see how the system is taking it on the high and low side. (well...it takes it on the low side and will react on the high side...never try to put refrigerant in on high side b/c it'll try to pressuring the can more and can be dangerous)

best of luck to you....also, cleaning out the lines isn't "necessary" but it would sure stink to install a compressor yourself with no warranty and ruin it quickly because the system is full of crud. Don't even ask me why I'm giving this warning!!! I've done a number of AC jobs on my own and a few of my friends cars. Luckily I learned the hard way on my own car!! I guess it's possible the compressor I bought was bad(that's what I told to store to get another one) but thoroughly flushing the system did the trick for me.

[KillerKeller_jr]

Thanks for the tip...I won't be running the system anymore until I get it in for service and replace the Orfice tube. I did get one but forgot to replace it before charging the system to check for leaks, not sure why I forgot, part only cost $2...I'll just have the shop replace the orfice tube with the one I bought. Hopefully I can get this all done rather cheaply...on a tight budget with a 4 month old and all, I am getting it fixed for him since I take and pick him up from daycare. As for checking for leaks tried the old soap and water trick to check for major leaks not the minor ones...the shop can check for those when I take it in. Again thanks for your tips.

I too have assisted with fixing several A/C systems or topping them off but always recomend to go to a professional for the final step of vacing, recharging and checking the system for leaks. It always saves you $$$$ in the end.