slowmanvns

1996 SE - So I gave my max to my nephew and within a couple of weeks, the alternator went. I find the videos on replacing the alternator from the bottom as the correct procedure which includes lowering the compressor for access and gave these videos to my nephew to use, but kids these days as they are, his novice, would-be mechanic friend goes thru the top and was able to change it but he had to disconnect one of the AC lines (don't know which), saying just to add refrigerant after he had reconnected the hose. my Nephew added three cans and it sucked them all in. AC worked initially he says, tho not very cold but now it is not. I told him to take car and have a full evacuate and recharge. He did go but the ac shop said the compressor is shot. Any help to verify the compressor is dead is appreciated.

JvG

If it worked before he disconnected the line, the compressor should be fine.

Perhaps all it needs is an o ring where his car butcher disconnected it. Of course now he needs a new dryer, an evacuation, and a refIll at a shop.

Please tell him to use a different dyi mechanic.

DennisMik

iTrader: (2)

There is an oil that is in the a/c lines to lubricate the compressor. Taking off the hose and letting all the refrigerant blow out also lets the oil out.

Was oil added when the refrigerant was replaced? If not........

JvG

Good point, Dennis.

If the compressor was not broken before it was disconnected, it might be ruined now due to lack of oil.

slowmanvns

No oil was in the added refrigerant. I guess that was the cause of it going bad. I will have him take it to a second shop and see if they agree the comp is bad

allmazda

3 cans is way too much. Charge I believe is 22 ozs.

slowmanvns

He put in the first can only at the beginning of February using an attachment with a pressure dial and it took about 15 minutes to empty because of the cold weather I guess. The pressure reading never got to the correct "green" area of the dial. He didn't put in the other two cans until about 3 weeks later when it was warmer and they emptied with 3 minutes each. I have feeling there is a leak somewhere so he's going to try using a uv dye refrigerant to spot any leaks even tho the ac shop said the compressor is shot.

DennisMik

iTrader: (2)

I hope it is something simple like a leak because a rebuilt compressor is expensive.

allmazda

On ebay you can find one for around a 100 shipped. I got one and it works great.

reallywildstuff

This thread has been hard to read. I hope this would-be mechanic "friend" that let the magic out of the A/C system is having to sweat it out somewhere with your nephew while he pays for the damage he's done to his car.

Given the exhibited level of competence by this person, it is unlikely that a new o-ring, dipped in oil, was used upon re-assembly so I would focus on that area with the U/V detector. Was this system even evacuated before the new refrigerant was added?

Assuming the re-assembled system was fed enough refrigerant to cycle the clutch - that's bad news for the compressor re: no oil being added at the same time. PLUS the dryer was exposed to atmosphere for who knows how long...

I'd find the leak, add the required amount of oil to the compressor while the system was open to fix the leak, fix the leak, and then _maybe_ proceed with the expense of an evacuate/recharge without additionally changing anymore components. If it works it works.

If it doesn't work, he'll need to change the compressor and dryer at the same time to be happy. Also new O-rings for everything that's opened. There's probably oil pooled in the bottom of the condenser coil...there's probably a chart somewhere for how much oil to add vs. what parts have been replaced.

DennisMik

iTrader: (2)

I wonder if it is possible to say that replacing some part will require you to add some specific amount of oil.

If you are opening the system and replacing parts, you should evac the system to make sure there is no moisture. After an evac, there is no oil, so you need a complete refill, 8.5 oz.

BobMax

There's a subtle difference here in what "evac" means... you should vacuum the system down until all the refrig is pulled out and the moisture becomes water due to the pressure change and flows out with the vacuum. But that doesn't usually pull the oil out, it's heavy and it sits in the pipes and compressor. You can also clean the system with a flush, removing all oil.

At this point it's anyone's guess as to how much oil is in there. There are charts for most cars (maybe in the FSM) saying "when you replace xyz, add this much oil" but it seems too late for that. Depending on where that hose was you may have lost a lot of compressor oil or almost none.

The drier is really a one shot deal. It has an absorbent material in it. Once that material is saturated, that's it. It's really only supposed to have to absorb the water that's erroneously introduced in charging. When you vacuum, most of the water comes out. The little vapor that's left is pulled out in the drier.

When you open a pipe, you are supposed to stick a rubber plug in both sides almost instantly. Otherwise moisture gets in and it's time to change the drier.

I think at this point you have two choices: Either redo this repair correctly, or get a compressor and redo it correctly.

Option 1 requires discharging, removing the compressor to dump the oil from that (unless you can do it on the max without removal), flush, replacing that o-ring with a new one properly lubed, new drier & o-rings, refill with oil, recharge with proper amount, and watch the gauges. If you are lucky, the compressor is OK and it works.

Option 2 is the same thing, but you replace the compressor instead of just draining the oil from it.

FYI- the flush is required by most compressor warranties. I'd change the expansion valve too if you are going to all this trouble since they can wear and you're pulling it all open anyway. For $12 you might as well include it.

If you go with option one, you take a risk that the work is all a waste if you find the compressor is bad. So, your time, $8 drier, $12 refrigerant, $5 oil. Not too much money unless you have to pay someone - they usually charge $150 for just the vac/charge. If you go with option 2, you pay $200 for a compressor. but it likely works (unless you have another leak somewhere).