AC repair tools

[JointTech]

My AC is getting really weak. r134. I used one of those AC Master cans from the parts store and followed the directions to add refridgerant. I added probably half a bottle and then it started blowing really warm air.
The gauge on this POS bottle is basically useless and I think I over filled it. I recovered some back out and its back to blowing mildly cool air...
Im thinking I want to vacuum the system and fill it up.
I was looking at hoses and gauges on amazon and cant figure out what I need.

I have a vacuum pump. I dont plan on filtering the 134 ill just get new cans.

What set of gauges/manifold would you recommend? Some look like they only work for filling.
Do I need low loss fittings?

[MARKDTN]

You need a set of gauges. like
Amazon.com: Mountain 8205 R-134a Brass Manifold...
This will allow you to check pressures on both sides of the system, charge, and evacuate. If you have an older vacuum pump, you may need an adapter fitting or to make a hose with the correct ends.


Parts stores should be banned from selling that one-stop-fix-all-in-a-can. Useless as mammories on a male swine.

[motorcritter]

The 'do-it-yerself' A/C stuff is great- for A/C repair shops who get to correct all the damage from shooting a load of sealant, possibly the incorrect (amount and/or type) of oil and an amount of refrigerant that is probably too big or too little. Get a vacuum pump, a set of gauges, a book on mobile A/C systems (Chilton or Haynes has one, IIRC), some flush solvent, a kit for conversion (valves, o-rings, gaskets), a new receiver/dryer, the proper oil and some R134a. These systems ran R12, and conversion is possible, and can even produce good results- so long as attention to detail is maintained. Oh, yeah, a leak detection system- either visual with UV light and dye or a 'sniffer', fix whatever is leaking or broken, and add a high-pressure switch to the system. Then enjoy the cold comfort of mobile air conditioned luxury! It seems like a lot of investment, time and money-wise, but worth it in the long run. If you can borrow the tools, so much the better.

[JointTech]

this is actually in my 04 Scion just didn't have any other friends to ask but the chevy guys.

[BluTrukker]

There is something to be said for doing it yourself, and buying the tools to use in the future. BUT, how much AC work do you expect to do in the future? Looking back, how much would you have used it in the past? If you only need to repair AC once a decade or so, than having the tools may not be the best solution. The cost of all of the equipment to fix it will probably be the same as taking it to a licensed AC repair shop and having it diagnosed/repaired 1 or 2 times.

[piecesparts]

I am a tool nut. If I have to buy and ONLY use it once, I feel that I am leaps and bounds ahead of the game. R134 is what many would refer to as a "Critical" gas. IT is really a touchy thing to deal with. If you overcharge it will not work and if you are under charged, it will not work---thus the critical thought process. R12 was a real deal, it worked even if the unit was full to the brim and the compressor was getting liquid back to it.

I don't have a vacuum pump, but I do have everything else to work with freon.

[JointTech]

i just like having the tools even if I just use it once. But Im sort of getting into flipping cars and helping out friends and family now that I have a decent sized shop and tools. So I figure I might as well buy the AC stuff.

[JointTech]

got a decent set of gauges and a couple 12oz cans of 134a. Hooked up my vacuum and pulled it down around 29in.
It held a vacuum for a few minutes so I figured its good on leaks.
I started refilling it and got to the pressures shown here with less than a full 12oz can. probably an ounce left in it.
The car cools at 2000rpm+ pretty well. I was fine driving home and its 95 today. At idle though its not that cold.
I measured it at about 55.6deg at 2000rpm. which seems high but better than it was.
Im thinking the compressor is dying..

[spatz]

Since it held vacuum for a few minutes did it raise by itself or did you start adding 134a to the system. I used to vacuum the system to to minus 29, walk away and have a cup of coffee.by this time 5 to 10 minutes have gone by and the needle hasn't raised its good to charge. If the needle moved there is a leak somewhere in the system. I would say its low on freon should be just over a pound ti fill it. there should be a sticker on the vehicle with the amount of freon to use unless its gone missing

[JointTech]

the scion dealership said 13oz max. I didn't get a full 12oz can into it.
What I cant find is the factory specs on what the pressure should be.
the pressure went up as I added Freon.
I pulled the vacuum for 5 minutes or so and then let it hold for about 5 minutes. it held.
This picture was at idle. If it gets to 1500-2000 the pressure will drop down about 10 points.

[LEEVON]

Unfortunately, pressure readings can get you close, but they are still subjective. The best way is to evacuate what's in the system and add the correct volume by weight...sorry I forgot my Identifix password or I would go grab the spec for you. We see cars in the shop all the time that can be as little as 8 ounces high or low and not cooling efficiently.

[leddzepp]

If you are going to do your own AC work, stock up on R134 next time you are in Vegas. It's $5 a can there as opposed to $20 + $10 deposit per can here .

[frank69]

Check out the pawn shops, just do a little research and try to find a quality set of gauges.You should be able to save at least 50%

[jjzepplin]

Subbed for info on not so cold at idle.

[brown7373]

I also bought a set of LARGE crow's foot wrenches. It makes removing and then retightening the fittings on the lines a lot easier. Problem I was having was the fittings nuts are large, which means a large (and long) wrench was fitting the hood, or hinge or other parts. Crows foot made it a lot easier to change the line O-rings.

[dmartin1]

oh yes much cheaper refridgerant out of cali.

[67ChevyRedneck]

Originally Posted by LEEVON

Unfortunately, pressure readings can get you close, but they are still subjective. The best way is to evacuate what's in the system and add the correct volume by weight...sorry I forgot my Identifix password or I would go grab the spec for you. We see cars in the shop all the time that can be as little as 8 ounces high or low and not cooling efficiently.

My Vintage Air kit had a leak (Schrader valve on suction side was stuck open a tiny tiny bit) in my 65 mustang, and the above is the same thing the A/C guy that fixed it told me. He pulled everything out, it held vacuum for 20 minutes (had to wait on new valve, they were out of the one I needed) then refilled it per the vintage air specs. Nice 'n cold again now.

[Bigdav160]

Right there on the gauge I can see it's 52º. That's too warm.

Either your condenser has insufficient air flow or you're slightly overcharged.