Long story short... I've had car for 2 years, no a/c. First summer with car, I put in 2 cans of refrigerant and it cooled for a few weeks. Leaked out.
Year later, put in another 2 cans as well as some Stop Leak. Barely changed the temperature inside the car. Still felt like outside air.
Took it to a shop, they put in another can of freon, and some dye. Could not find a leak. Said compressor didn't show signs of leaking, and the hoses seemed fine, the condenser also seemed to check out okay. Told me to drive it around and wait for dye to show it's ugly face. Drove home, popped hood, "why, hello there dye!"
Seemed to be coming from the dryer/accumulator/silver canister (it's been named so many things everywhere I go) valve. Was told valve MAY be able to be replaced. Was also told, it probably cant be, but the inside piece, the... cant think of the name of the tiny itty bitty piece, can be replaced. I don't think it's leaking from the valve, or out of the valve, but more so from around the valve. So, I think if I replace the entire unit (dryer/accumulator) I'll solve my problem, as well as preventative maintenance.
I KNOW I need to release the freon from inside the system, as it's all under pressure. I can rent the vacuum pump from Auto Zone and I plan to, and I can get a new accumulator for $91 at an AC Delco shop. I don't think this job looks too terribly hard to do. Just need some insight on anything special I need to do. I realize, vacuum all freon out, unhook hoses, install is reverse of removal, then recharge with more freon. Is that all there is to it?
Thanks for any insight...

 

man not hard to do. let the freon leak out. I just got a new dryer from oreily's for $39 bucks. Change it and the new dryer comes with new orings. I would even change the orfice tube since your opening the system. Then get 3 cans of refrigrent and vacuum and your done. Should take no longer than 1 hour at the max to do it the right way.

 

No, that's not all there is to it.

You'll need a charging manifold and it's gauges, too. When you pull vacuum, you need to be able to measure how deep the vacuum is, and is it holding. Pull vacuum to at least 29.5" Hg, and hold it there for at least 2 hrs., 4 is better. If the system won't hold vacuum (as in vacuum pump off), it absolutely WILL leak refrigerant, and probably a couple of other bad things will happen, too. This level of vacuum is necessary to get all the moisture out of the oil which circulates freely throughout the system - and the level of moisture isn't great, either. More like a tiny bit of water vapor, which can and will really screw up the system by freezing at the outlet of the orifice tube. When this happens, it either partially or wholly blocks the tube, so either not enough or no A/C.

The vacuum also clears any air/non-condensible gases out of the system. In sufficient quantity, these gases will cause the system to shut down on the high pressure switch.

 

Either of you got pics to go with what you are talking about?
Explain the vacuuming process plz? I thought the vacuum was to suck out all the old freon?
Are you guys referring to the a/c vacuum pump that's near the firewall?
What's the orfice tube? I thought the orfice was in the valve?

 

the orfice tube is in the line going to the evaporator. the dryer is the big silver thing by the battery and fender. If you have a good vacuum pump(don't know how good theres is) i use snap on's. A good vacuum is 30 minutes. and manifold gauge set you do need.sorry forgot that.

 

This isn't going to be as easy as I had hoped. Lol. Damn!

 

You're confusing vacuum with freon recovery, which is required by law if you do this sort of thing in a shop on a professional basis. Recovery collects the old refrigerant so that it isn't expelled into the atmosphere. Recovery machines do have a vacuum pump in them, but they also can't be rented and cost a couple thou. Doing it this way in a shop is law, and requires the tech to have a federal license.

At home, you just blow the freon into the air from either the HP or LP side of the system. The follow on vaccum is to remove moisture, air and non-condensible gases from the system. 30 mins is NOT a good vacuum.

Hook a vacuum pump to a charged system, and bad things will happen!!!

The orifice tube is what controls the flow of freon as it enters the evaportor.

 

I was told at Autozone that they rent out the (they referred to it as the vacuum pump) "recovery machine" as part of their "rent-a-tool" service.

 

Well, they may rent out a recovery machine...but I doubt it. Probably just a vacuum pump. Remember, there is seldom any intelligent life to be found behind the counter at AutoZone, so there's no telling what they mean.

 

You bring up a good point. Well, I guess I wont be doing this myself tomorrow then. Gotta find a trust worthy, reliable, and not too damn greedy shop to help me out!

 

dude this isn't a hard job to do. you need 2 different size wrenches to break the 2 lines loose to get dryer out and then new dryer. vacuums can be found a harbor freight(but they aren't the best, but will get job done just leave the vacuum on for couple hours), and manifold gauge set can be had for $40 bucks. You will pay this for a shop to do this job plus more. Buy the tools and have them for next job. Thats my motto.

 

It's not really difficult as Choppers says. And the tools aren't THAT much, as long as you stay away from the Snap-On truck. The Harbor Freight pump may not last 10 years, but you probably aren't going to use it every day, either.

 

I'm going to swing by a shop, or two, to get a few second opinions to make sure I'm replacing the right part.

 

After all, no sense in dishing out money on parts that don't completely fix the problem right?

 

Absolutely, there is nothing like someone being there to actually look at it.

 

Thanks for the input guys. I took it to this guy I was referred to by a part's store. Took all day, thanks to a little obstacle, but no biggy. Had to replace the dryer, and my orfice was clogged up beyond belief. Which is probably why when I put in freon, it didn't do anything. None of it was able to work it's way through the system. Built up pressure, caused the dryer valve to leak. At least that's my theory anyway.
This guy does good work, very nice, stands behind his work, and has had plenty of experience with working on fbody's. I think I've found myself a new mechanic...
Thanks again for your info! Maybe when I get more money, and can invest in tools I'll only use once... I'll try and do it myself... haha.

 

Any idea what the orifice tube was plugged with? That's not normal.

 

Guy and I THINK that when I used some Stop Leak, a few months ago, that's probably what did it. Or, if maybe the previous owner did, and then when I did it... it all got clogged there.

 

Got it. That's like using radiator stop leak. A band-aid patch that doesn't fix (and never will) the problem, and will usually cause problems of it's own.

 

im doing ac on my car
first of all its completely empty
is it highly recommended to buy a new drier?