A/C not working, History unknown, self charge or let a shop do it?

[VIIIup]

Had my '96 for close to year and the a/c hasn't worked from day one. I have no idea how long it has been non functioning. Will it be safe to charge it myself or will I be better off letting a shop do it? I don't have manifold gauges or a vacuum pump. I'd hate to throw a couple of cans of freon in it and it be low on oil and destroy stuff.

What say L.O.D.?

 

[Jamesvinar]

Chances are it's the Blend door. If you go in behind the glove box and to the left there should be a little lever you can move by hand and open it up to let the cool air out

 

[VIIIup]

There is no question it is low on/out of freon, I'm more worried about it being low on oil and ruining the compressor

 

[driller]

You want to take it to a pro and have them evacuate, purge and fill the system. Don't be surprised if you need an orifice valve or find a leak somewhere. It'll cost somewhat but in the long run it will be worth it.

 

[ONLYTONY]

When the ac clutch engages, but doesn't stay in, and kicks on and off, is normally low on Freon. As you add Freon, it stays engaged for longer periods. Most stuff you can get off the shelf, has some oil in it. Turn it to max ac, car running, and time the clutch. 3 seconds ,real low, 5-8 seconds, not too low. I nursed my 95 for years, just adding 1 small can, and every year a little more. When it got to 1 lg, and 1 small can, I knew it was time, and had Bruce change the whole system. WARNING, if you overfill you can blow the compressor.

 

[beerdog]

You can buy one of those kits with the fill gage and valve to charge the system. Since there is no refrigerant it has a leak. No A/C system is supposed to loose its refrigerant. You just do not know how bad the leak is. You may have a very small leak and a simple recharge will last you a year or you may have a major leak at it will not work or last more than a week. As stated, many people (me included) have nursed along AC systems by doing the DIY recharge method. You do not want to do this if you have recently changed major components such as the compressor.

The right way is to purge the system by pulling a vacum. This removes all old refrigerant and moisture. Then perform test to check for functionality and leaks. Fix what is broken or leaks. Then properly recharge the system. All of this should be done using proper gage set-up to measure the high and low side. A cheap gage set-up will cost you $100+ and you need to learn to use it. Watch some videos on you tube to get an understanding. This s what is needed to get the coldest air and maximize efficiency.

 

[VIIIup]

I've got the screw on thing with gauge that you use to recharge on your own. I've just never invested in manifold gauges and a vacuum pump.

 

[Bangster]

Since it is AC weather again, I just had to add a can to my 2000 Grand Marquis. The compressor was cycling about 75% of the time. I have a full gauge set and a vacuum pump, but I just added 12 ounces of R-134 (4.88 a can at Walmart, didn't feel the need for the 30 dollar Freeze AC and the other stuff) and that got the pressures close (I would likely add a couple ounces closer to summer and 100 degree temps).

When I first got my 97 Mark VIII, the AC blew warm. I could see that it leaked at the port on the accumulator. I made sure it was tight, then put it on a vacuum for a few hours, made sure it held over night, then added freon until I got the high and low side pressures right. I did add a can of leak detect, and looking at the amount of oil under the leak added 2 ounces of oil.

 

[VIIIup]

Learn something new every day. Didn't know they made vacuum pumps that run off your shop air compressor, and they are way cheaper than the electrics. My friend has gauges, I have a compressor, snag one of these pumps and do it right.