1998 Subaru Outback A/C Compressor Seized

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Colin

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1998 Subaru Outback A/C Compressor Seized
Two questoins: Is it possible to get a used compressor at a junk yard and would it be difficult to put in myself?

Colin
 

Paul

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You probably could,but you may just be buying the same old piece of junk.You are going to be farther ahead buying a new or reman compressor.Once the a/c system is opened up,the receiver dryer needs to be replaced.Once the new parts are installed,a vacuum pump is required to remove the air from the system and it has to hold that vacuum for a time.If it doesn't you have a leak and that needs to be taken care of.You're looking at roughly $400 for a reman compressor,the RD runs about $30,plus various new O rings.

If you want an a/c system to work properly,the work and the parts have to be quality.
 

2POINTautO

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Just a little help deciding. This is general to AC, not necessarily 134 only.

Evacuate and Charging Procedure.

Attach AC 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 AC vacuum pump. Open both of the dials on you’re AC 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.

My personal procedure will include is after 30-40 minutes evacuate I add 1/4 lb Freon and recover and evacuate for 45-60 minutes I think this gets trapped vapors in system. Water vapor moves slow in heavy vacuum. This is the minimum suggested method. ALSO IF YOU VACUME BELOW 70 DEGREES OUTSIDE TEMP IT WON'T BOIL MOSITURE OUT . When system has achieved a state of 29.9 hg’s of vacuum close both dials on the AC gauge set. You may loose up to 1 hg for every 1000 feet above sea level depending on the capacity and quality of the vacuum 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 vacuum (zero pressure) 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. Depending on your gauges being either metric in mpa or kpa, or being in PSI you may notice that in the vacuum range the reading is not very accurate, for this reason I like to move on to another job or go to lunch at this point and give extra time for the system to loose its vacuum if it is going to leak. Also if there was any Freon gas trapped in the system after only a short evacuation then as the temperature rises within the system, the Freon gas will produce pressure making you think that you have a vacuum leak. This is the reason why you should make several attempts to evacuate the entire system. Some technicians will even use a heat gun to raise the temperature of the components where moisture may be trapped such as an accumulator. Setting the blower on high speed will also help boil out trapped refrigerant. The cooler it is the harder it will be to boil the moisture out. This is a really important in the cooler months I often get some heat into the components. When relieving the vacuum you should not let the atmospheric pressure in along with its moist air. I like to hook up a can of Freon at the very start of this process in preparation for the Freon to add pressure while relieving vacuum when I am confident of the evacuation process the Freon can is already in place for final charging.

You can already have your Freon connected as mentioned above or follow this procedure if you don’t have the extra hose to the Freon can in advance. 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 at the gauge set connection!

Open only the low side dial on you’re AC gauges allowing refrigerant gas 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 AC 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, but first give a minute or two to allow the system electronics to do its job, sometimes the compressor does not want to come on right after charging the initial amount of Freon gas. 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! You should not charge over 45 PSI at any engine speed, if your LO side pressure is over 45 PSI and you are required to service a liquid Freon then monitor your pressure extremely closely. When you pour liquid into the system by turning your can upside-down you must only allow the pressure to raise a very little bit and do not shake the can at anytime. If you are able to put your Freon container into a hot water bucket then this will be your safest procedure to increase the gas pressure within the can forcing only gas into your newly evacuated and possibly newly repaired system. 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. (somewhere between 2.2 ~ 2.7 times ambient temperature should be the maximum requirement)

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! Make sure heater cable is adjusted properly.

In lower ambient climates, doors and or windows of the vehicle maybe required to be open to achieve proper cooling when charging the AC system. In ambient temperatures below 70F I recommend extra caution while servicing, Freon temperature / pressure relationship will be lower than expected, rechecking your results on a warmer day should be in your final check of systems ability to cool properly or to the best of its ability.


Vacuuming with shop air and a special tool to create vacuum. The other more important need to evacuate is to remove all the moisture from the humid air that entered the system during the repairs. The universal method or requirement on vacuuming is to draw a vacuum down to 500 microns I believe is the newest measurement and the tool that was mentioned is not strong enough to draw a vacuum that deep. Water boils in a vacuum and that is the purpose of drawing a vacuum, get the moisture out to prevent it from freezing inside the system and plugging it up during normal operation. This is also one purpose of the receiver / drier if your car has one, the desiccant will soak up the moisture but it has a limit of its sponge like abilities. It is normally changed as normal maintenance while performing other maintenance. A little extra theory is that the oil in the system also holds moisture and may require several vacuuming cycles, vacuum - add a touch of Freon to create near zero pressure - vacuum - maybe repeating a few times to be completely sure of a dry system although I have only heard of a select few going this far with medium strength equipment. Don’t forget to install your gas can to the gage set and connect it to the vacuum pump to clear air and moisture from the service hoses too. Once final vacuum is complete, crack open the can and start servicing, try not to let the low pressure go over 45 PSI unless you are forced to.

Topping off any system is a bad idea. Where is the leak. Let's stop the leak and then address the moisture and amount of oil in the system problem and you want have a failure. System clean, free of moisture, correct oil and Freon charges and no leaks, making sure there is proper air flow at condenser and evaporator and no problems with blend doors is a key to success in this business.

Sales pitch. First we don't give prices over the phone but if you'll bring the car by we will be glad to check the AC system out for you. By the way if the Freon is gone then you must have a leak and at today’s prices for Freon you will want to stop the leak before adding Freon to your vehicle. It is also very important to note that if it has lost the Freon it has also lost some of the oil and as you know the oil in the compressor does the same thing as the oil in your cars engine. Some folks are not aware that there is special oil in their AC system.
 

jjm

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As Paul said, you'd likely be getting someone else's junk, especially after nearly 10 years, and the receiver / dryer needs to be replaced, and possibly the expansion valve, depending on if there's debris in it. All the O-rings need to go (cheap) and the system needs to be flushed.

Try giving Tim a call at <a href="http://www.ackits.com" target="_blank">www.ackits.com</a> at (602) 233-0090, or e-mail to trb@ackits.com. I don't see your compressor listed on his site, but I'm sure he can get get you a deal on a new or quality reman. Stay away from chain store remains, unless you like changing out the same parts over and over again.

You will need some tools for the job if you're not going to have the evacuation and recharge done professionally:

<img src="http://www.autoacforum.com/diy/diy1.jpg">

<a href="http://www.ackits.com/merchant.mvc?Screen=PROD&Store_Code=01&Product_Code=DIY-STARTER1&Category_Code=DIY" target="_blank">DIY Starter Kit </a>

<img src="http://www.autoacforum.com/diy/diyadvance.jpg">

<a href="http://www.ackits.com/merchant.mvc?Screen=PROD&Store_Code=01&Product_Code=DIYADVANCE&Category_Code=DIY" target="_blank">Do-It-Yourself (DIY) Advance Starter Kit</a>

<img src="http://www.ackits.com/tools/images/66773L.jpg">

You're better off with the tools in my opinion, because if you do something wrong and there's a leak, a shop wont evac and recharge a second time for nothing. Before long, you could've bought the tools and did the whole thing yourself.

Joe

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