Help: 99' A/c Compressor Freon Fill Tips

[kool7]

Hi All , I need some tips on how to add the oil and freon for a 1999 blazer. Picked up a compresser from auto zone and was wondering how install the stuff to get me up and going ..

how much oil ?
how much freon ( cans) ?

thanks much !!! joe in las vegas ....

[RahX]

First, make sure the compressor doesn't come filled with oil. If it comes dry, with some assmebly lubrication, get some PAG oil and put about 3 ounces in the plug on the side. Run a bit of that oil through the intake port of the compressor itself. You will want to get ahold of the clutch in front and turn it over a dozen times or so to lube up the front bearing and such. Now before you put the compressor on, what went wrong with it? Did it frag out? If so did you replace the orifice tube and backflush the system really well? How about the drier? It doesn't take much moisture to overwhelm the dessicant pack in the drier not to mention metal shards ripping the pack open. Anyway, you'll need to pull a vacuum on the system after everything gets hooked up(don't forget to put the high/low pressure switches on the new compressor if it has them) Run it for about 15 mins and shut it off and let it set and make sure it doesnt lose vacuum. 2-3 in/hg loss is acceptible. After that look on the fan shroud or somewhere in that area for an a/c system sticker it'll tell you how much r134 goes in. If you're canning it, 16oz is a pound. Fill on the low side. You will want to try and get as much in the system as you can before you start it up. Let it sit for a min after you get it filled before you start it to let the r134 vaporize so the compressor doesn't suck a bunch of liquid r134. After that, add until its to the right amount and you should be good to go. More=bad less=bad try and get it as close as possible. should be about 1.5-1.75lbs. If you don't put enough, the system won't cool properly and there wont be anything to carry the oil through the system. Too much and it won't cool properly and you run the risk of blowing something apart And pulling a vacuum on it is a MUST. Air doesn't work in these systems. Anyone see anything i'm mistaken on or forgot?

[kool7]

Wow , That that last post was a big help !! Thanks !

Thanks all for the help .. where the intake port ?

[RahX]

where the line goes onto the back of the compressor. It should have a screen in the intake side of it. If not turn the clutch clockwise and feel which one sucks. :P

[Mango™]

Is it easy to replace a clutch plate on a the compressor? Or is it easier to get a rebuilt complete assembly AC system?
91 s-10 187k miles v6 4.3 liter

Thanks

[RahX]

the clutch is easy to replace. but it requires some experience because its kind of awkward to explain. you can have someone replace it on the vehicle without discharging the system.