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Hi everybody! The compressor on my 95 Sub was dead and I bought one on ebay. It got installed it worked great, but it started making noises after 2 months. The guy on ebay sent me a new one, no questions asked.

Now the problem: my front AC is freezing cold, but the back is hot. Arer there 2 different Freon tanks? should I just get the back recharged?>

Thanks for your help!

Alex
 

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Wow, that's good service. Who did you buy it from on eBay?
 

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The front and rear a/c systems use the same freon system, but if I remember correctly, there is an orfice tube for the front and another for the rear. If the rear orfice tube is plugged with debris from when your compressor failed it could cause the problem you are describing.
 

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Hey Ale70, How difficult was that installation? Any specialized tools or is it pretty straight forward? I need to do this on mine.
 

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The installation itself is easy, but you will need a vacuum pump to evacuate all of the air and moisture from the system before you recharge it. You should also have a set of a/c gauges to show you what your high and low side pressures are. I am in the middle of doing my dad's '94 right now. Should finish it tonight.
 

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Just bought the vaccum pump and the gauge set off ebay for about $80 including shipping, as soon as that stuff gets here I will hit up the guy with the AC kit and see if we can git - r - dun ;-)
 

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If you got the pump and gauges for $80, you got a smokin' deal!!
 

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What do they go for typically?
 

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The gauges will go for around $75 at O'reilley's and the pump can start at about $125 and go up from there depending on what you get.
 

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The guage price was pretty close to what I paid the pump was only $10 and then another $10 for shipping. I have the gauges but the pump has not showed up yet..... maybe thats what I get for $20 ac pump.

anybody got any great tips on how to actually do this? Gary you wouldn't happen to have those instructions in an electronic format would you?
 

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This response is from the www.ackits.com forum. Your system (if you have rear air) should hold 11 oz. of pag 150 oil and 64 oz. of r-134 freon.

Here is the procedure:

Evacuate and Charging Procedure.

Attach a/c manifold gauges to the vehicle. Make sure you attach the correct hose to the proper service port. This is very important to prevent personal injury! Attach center (Yellow Hose) to a UL approved a/c vacuum pump. Open both of the dials on you’re a/c manifold gauge set. This will allow the system to be evacuated through both the low and hide side of the system. Turn your approved vacuum pump on starting the evacuation process. 30 minutes usually will be enough time. If vacuum pump has ballast read the owners manual concerning this option.

When system has achieved a state of 29.9 hg’s of vacuum close both dials on the a/c gauge set. You may loose up to 1 hg for every 1000 feet above sea level depending on the capacity and quality of pump. At this point wait 5 to 10 minutes letting the vacuum boil off any moisture trapped in the refrigerant oil. This is also a good time to watch and see if vacuum has returned to a zero state. If so you need to check for leaks in the system. Assuming the system is holding a vacuum after letting the moisture boil off repeat the evacuation procedure again. This process may need to be done a few times before all moisture has been removed and you see no degradation in vacuum after closing both dials for 5 to 10 minutes.

With both dials closed remove the center charging hose attached to the vacuum pump and connect it to either a can tap and refrigerant or 30lbs refrigerant cylinder. Open the valve on either the can tap or 30lbs cylinder allowing refrigerant into the charging hose. With refrigerant in the charging hose slowly crack this hose at the manifold gauge bleeding off any air that may have gotten trapped when moving from the vacuum pump to the refrigerant source. Only the slightest amount of refrigerant should be released in this process so be sure to tighten the charging line quickly!

Open only the low side dial on you’re a/c gauges allowing refrigerant to flow into the system. Again I stress the high side must be closed or you may cause personal injury to yourself or others! Start vehicle and turn on the a/c system with blower on the highest speed. In some cases if the compressor clutch has not engaged you may need to by pass the low pressure cut out/cycling switch. Refrigerant should be charged as a gas but in some cases it may be necessary to charge as a liquid. Be careful not to slug the compressor with liquid refrigerant! Charge system to OEM amounts and pressures if you are using the refrigerant the system was designed for. If vehicle is has been or is being converted start with about 60 percent of the original charging amount. After getting 60 percent of the original charge slowly add an ounce at a time until you reach the best possible vent temperature and pressure readings. If you do not know what your systems operating pressures are you can use the 2.2 x the ambient temperature as a guide. This should only be used as a guide as many systems will need more or less refrigerant to achieve proper cooling.

Having a weak fan clutch or an inoperative electric fan will cause system pressures to be incorrect. So make sure these components are working correctly before charging a system!

In lower ambient climates, doors and or windows of the vehicle maybe required to be open to achieve proper cooling when charging the a/c system.



Hope this helps.
 
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