Fixing the AC system - Frustrated
 

The seal on the front of my AC compressor went bad, so I bought a new (used) compressor. I haven't installed it yet, but I would like to very soon.

Everywhere I look says I have to replace the dryer at the same time for reasons guess I understand, and it is supposed to be a pretty cheap part. Unfortunately, Mazda attached mine to the condenser, and the combined part is not cheap.

Also, I cannot find anywhere to rent a vacuum pump. The nearest shop that does AC systems wants between $150 and $200 just to charge the system, and they couldn't even find the drier/condenser part so that would just add to the cost.

Can somebody who understands automotive AC explain my options please? This is my DD so I want to keep AC, but I don't have the hundreds of dollars to dump in it right now to have it repaired by a pro. This would also be the first time in many years that I would have to bring a car to a shop.

Can I just add some kind of universal drier? Where can I rent one of these vacuum pumps (I got scoffed at by everybody I called except autozone, who said it was listed in their rental list, but not in their particular inventory)? I am willing to give the new compressor a try without replacing the drier so long as my odds of success are decent, so I won't open the system until I have a plan I guess.

Sorry for the rant, I just really don''t want to bring this car to a shop and pay them $500 to overhaul the AC when I'm sure it's something I could do myself if I could find the tools.

Step 1: replace compressor

Step 2: Drive around town and offer shops $50 to vacuum your AC system until one (probably first one) accepts

Step 3: Charge AC system (either have shop do it, or pay $30 and do it yourself)

Step 4: Enjoy cold air

Step 5: Find the shop that is wallet-raping customers because they came up with the "you must replace more parts" crap, and punch them in the face.

buy these:
http://www.harborfreight.com/air-vac...ors-96677.html
http://www.harborfreight.com/a-c-man...set-92649.html
Then buy PAG oil and R134. I say to buy the equipment and do it yourself because a tiny leak will cost you more cash. I'm going to be forced to do this to my GF's Cherokee soon because the last shop she took it to charged $800 for a compressor and dryer, 1-week later and there is no 134 left in the system.

Can I get the PAG oil and R134 at the Auto Parts Store? This option is my favorite so far I think

That is exactly where you buy them, they probably have a "charge your AC system before the summer heatwave!" display next to the front door.

Not replacing the dryer when recharging is like leaving on the old filter when you change your oil. There's a reason that part is there, and if you recharge a system, you should replace it. Unless you use the A/C at least once a week, you need a functional dryer or you'll most likely have problems down the road.

But don't get one with sealant, just the R134. The last thing you want in a new AC compressor is shitty sealant.

Ordinarily, I'd agree with replacing the dryer. If you can get one.

I had the same dryer problem as skidude. I could not get a replacement that was compatible with my stock condenser. Ended up buying a used condenser (and used dryer) to replace my leaking condenser.

Whether you replace the dryer or not, the system needs to be evacuated. If you reuse the dryer, you need to evacuate the system longer.

I recommend using a vacuum pump and keep the AC system under vacuum for an hour. I have the HF electric vacuum pump. Well over 99% of the moisture will be removed due to the vacuum. You do need to keep it under vacuum for around an hour, or the water will not have time to out gas from the dryer internal surfaces, as well as the rest of the system, which may have been exposed to air and moisture. Heating the system (with a hair dryer) while under vacuum can further reduce the water vapor content. Just getting the plumbing warm can drive off an incredible amount of moisture. Don't heat it too much or you will damage the seals. You want it just hot enough that you don't want to leave your hand on it too long.

The vac pump that Hustler linked requires 4.2 CFM of air. If you don't have a compressor that can supply the air, then you will need to go with an electric vacuum pump. The electric pump is a LOT quieter than most air compressors.

DIY AC isn't that hard. If you f up, well, you can evacuate the system and start all over again. HTH

Or get lazy and hook up the AC to your inlet manifold and let a 21" vacuum suck away on that bitch.