Should I try to install a compressor?

[kimosabe55]

My AC compressor recently died and my local garage wants at least $750 to fix it. Being a college kid on a tight budget I'd rather fix it myself, but the most technical repair I've ever done was a simple door lock repair. This guide, http://www.explorerforum.com/forums/showthread.php?t=165354, makes a replacement seem pretty straightforward, but I was hoping someone who has done it before could tell me whether this is just too much for a noob or not. Am I likely to cause more problems doing this myself or is this something an inexperienced person could do?

 

[glfredrick]

Just installing the compressor is a no-brainer -- just a couple of bolts holding it down and a bolt holding the fitting to the back.

It is the other stuff that is problematic...

The system contains Freon R134a, which cannot be legally vented to atmosphere, which means that it needs to be suctioned out by a vacuum pump. (Note that a lot of home mechanics wink at this legality and dump to atmosphere... I do not advocate that practice.)

An inexpensive vacuum pump that will get the job done can be had at Harbor Freight (cost around $10 on sale). You will need one in any case if you intend to also re-fill the system with Freon.

Next, you need to add the correct compressor oil, which is specific to R134a systems. You will need to look up the type and amount -- generally a couple of ounces of PAG, but I may not be correct on that.

Then, finally (and this assumes that there are no other problems in the rest of the system as a result of the old compressor going bad, which may or may not be true) you will have to recharge the system with Freon 134a. To do that, you need to evacuate (with vacuum pump) the system, then introduce the correct amount of Freon, testing with a set of guages for that purpose, until you have correctly charged the system.

Can this be done at home by a beginner mechanic? Absolutely. I rate this job as about a 5 or 6 on a scale where 10 is the most difficult. Once the tools for the job are in hand, the rest of the work is fairly simple, and there are plenty of resouces to guide one through the process of charging the system, etc.

However, if you think that just swapping compressors and dumping in a can of Autozone freon will work, you don't understand the process and it won't...

 

[96eb96]

Just installing the compressor is a no-brainer -- just a couple of bolts holding it down and a bolt holding the fitting to the back.

It is the other stuff that is problematic...

The system contains Freon R134a, which cannot be legally vented to atmosphere, which means that it needs to be suctioned out by a vacuum pump. (Note that a lot of home mechanics wink at this legality and dump to atmosphere... I do not advocate that practice.)

An inexpensive vacuum pump that will get the job done can be had at Harbor Freight (cost around $10 on sale). You will need one in any case if you intend to also re-fill the system with Freon.

Next, you need to add the correct compressor oil, which is specific to R134a systems. You will need to look up the type and amount -- generally a couple of ounces of PAG, but I may not be correct on that.

Then, finally (and this assumes that there are no other problems in the rest of the system as a result of the old compressor going bad, which may or may not be true) you will have to recharge the system with Freon 134a. To do that, you need to evacuate (with vacuum pump) the system, then introduce the correct amount of Freon, testing with a set of guages for that purpose, until you have correctly charged the system.

Can this be done at home by a beginner mechanic? Absolutely. I rate this job as about a 5 or 6 on a scale where 10 is the most difficult. Once the tools for the job are in hand, the rest of the work is fairly simple, and there are plenty of resouces to guide one through the process of charging the system, etc.

However, if you think that just swapping compressors and dumping in a can of Autozone freon will work, you don't understand the process and it won't...

Good advice, replace the accumulator and orifice tube as well. Harbor freight has the charging manifold as well.

Also, depending on how the compressor failed you may have to flush the system or the new compressor will fail shortly. The $750 quote makes me believe you have a major failure and other parts may have to be replaced (a guess). The orifice tube can give you lots of clues on what you have on your hands. Some compressor mfgs do not honor warranties if you don't follow a flush routine and replacement of certain components.

First step is to relieve the freon though, and that must be done by a shop.

The orifice tube is located in the passenger side lower air conditioning hose that enters the evaporator. You need a spring lock tool to open the fitting. You pull it out of the evaporator side with needle nose pliers, taking it easy not to break it.

Make sure all the freon is out before you open any lines!!!!

 

[kimosabe55]

Thanks for the quick reply and all the good info guys. I'll give it a shot then once I find a decent compressor that ships quickly, looks like it'll cost about $150. I agree with you about the accumulator and orifice tube since the gunk in those will just cycle back into a new compressor from what I've heard, and I don't feel like doing this twice. I'm planning on letting a professional charge it since it's pretty cheap, and my local landfill disposes of freon so I'll take it to them. Anything else that compressors tend to damage when they go bad? I'm going to replace my serpentine belt just to be safe as well. Once again I appreciate all the help on this forum. Great community here.

 

[Maniak]

Its amazing whats on the 'net.. I found Video of how to replace the a/c compressor on a 96 explorer.

Search for "How to Replace an Air Conditioning Compressor in a Ford Explorer" in Youtube for a series of videos of the different steps..

~Mark

 

[kimosabe55]

Its amazing whats on the 'net.. I found Video of how to replace the a/c compressor on a 96 explorer.

Search for "How to Replace an Air Conditioning Compressor in a Ford Explorer" in Youtube for a series of videos of the different steps..

~Mark

Those videos are perfect. Now that I've seen what I'm getting in to this isn't so daunting. Thanks man.

 

[Cobraguy]

The system contains Freon R134a, which cannot be legally vented to atmosphere, which means that it needs to be suctioned out by a vacuum pump. (Note that a lot of home mechanics wink at this legality and dump to atmosphere... I do not advocate that practice.)

Not only that...it can be VERY expensive if you are caught. The majority of all fines for improper disposal of refrigerant (10 grand if I recall) are from Florida. I'm not sure how private individuals are caught. But they are...

Next, you need to add the correct compressor oil, which is specific to R134a systems. You will need to look up the type and amount -- generally a couple of ounces of PAG, but I may not be correct on that.

I believe you will find it takes 7 ounces of PAG 46 for the entire system. However, most quality replacement compressors come with a full oil charge. You MUST find out if this is true with your compressor as overcharging the oil will cause a lot of cooling issues.

Can this be done at home by a beginner mechanic? Absolutely. I rate this job as about a 5 or 6 on a scale where 10 is the most difficult.

I disagree with this. I guess if it's a straight compressor R & R and you have a Recovery machine, vacuum pump, gauges, etc, then this is true. But if you have had a compressor fail and you find metal on the orifice tube, then this can be a very long and tedious job. You will then need to disassemble as much of the system as possible and flush all the components you can. You will also need to install a filter to meet warranty on most new compressors. A/C work is called "gravy" by most techs as it pays well and is usually clean work. But when you get a compressor failure, it can turn into a chore. This is assuming you want it done right.

 

[Maniak]

If you mechanicaly inclined then yes I'd say it is doable.. and the parts replacemnt is no worse than changing a water pump, "might" even be easier.

But.. Step 1 is to take the truck to a shop and have them take out the r-1343. Some still do it for free as they keep it, recycle it and resell it.

My guess is that $750 price they gave you was for "not doing it right". If you lost the compressor that means you need to replace the accumulator (many people call it the receiver drier), flush the system, replace the oriface tube and if the oriface tube is full of black stuff you really should change the evaporator and condensor.

If you are goind do do the minimum I would at least do the oriface tube, accumulator, compressor and flush the rest of the system.

I don't know if they make a DIY flush "kit" or if you need to buy the flush bottle (which I bought for < $100). The flush bottle is a bottle with a quick connect air connection on one side and what looks like an air gun on the other side. You fill up the bottle with flush, and use air from your air compressor to push it through the system to get the gunk out. Evaporators and condensors don't exactly flush completely, but its better than nothing.

You can get $15 evacuators that work using your air compressor OR pay $250 or so (sometimes I see them much less) at Harbor Freight for r-134 evacuation pump (120V powered)

A manifold set is $39-$69 at harbor freight. and IIRC you need a $5 can tap (connects the r-134 can to the hose on the manifold).

There is a good sticky thread here on converting from r-12 to r-134.. Its a good read and once you read it, what you do after you "do the repair" won't seem so bad.

~Mark

 

[96eb96]

Kimosabe55~
THe other day I posted links to service manuals - download one of them and study all the pages on A/C service. You will learn so much.

 

[kimosabe55]

This may be a stupid question, but can I still drive my car a few miles after I flush it, assuming I don't let the compressor engage? Thanks for the manuals 96eb96, I'm downloading them now. I bookmarked that sticky but haven't had a chance to read it yet.

 

[team]

I ended up completely going through my 96 x's ac system after reading all the info. on this site, asking members for info., and taking my time. I had a slow leak and traced it down to the end shaft seal on the front of the compressor. At first I was going to replace the compressor but I figured why not take the compressor apart and try to replace the seal since you can still buy the seal. I was only going to be out 10 dollars for a core charge if I totally screwed up the compressor so I cracked it open. Everything looked really good inside, the pistons and their bores had no scratches so I just put a new seal in it and put it back together. I then put a new orifice tube, new accumulator, pag oil, and borrowed a set of manifold gauges and rented a vacuum pump from autozone and totally redid the system and it works fine (and I saved ~200.00 by not buying another compressor). This site and its members were extremely helpful and I learned a ton about ac systems. So I would say give it a try if you are mechanically inclined and if you feel overwhelmed slow down and ask some members for help. If all else fails you can just take it to a shop and let them finish it up.

 

[Cobraguy]

This may be a stupid question, but can I still drive my car a few miles after I flush it, assuming I don't let the compressor engage? Thanks for the manuals 96eb96, I'm downloading them now. I bookmarked that sticky but haven't had a chance to read it yet.

Yes. You can drive it until the cows come home. Just disconnect the connector at the clutch to be sure it won't engage. It shouldn't engage anyway since there will be no pressure in the system. And you can also disconnect the connector for the pressure cycling switch. But the fool proof method is just unplug the clutch and there is no way it can engage.

 

[DSteele41]

Hello Guys... I'm looking to replace my compressor as well. Recently if locked up. My Goal is to just get the AC Compressor Replaced so that I can put the OEM length Serpentine back on. Currently I'm by passing the AC Compressor with a shorter Serpentine Belt..... Can I just replace the AC Compressor with correct amount of Oil in it... just so that the Serpentine Belt is going in its original path around all pulleys.. Is this an option
"Just disconnect the connector at the clutch to be sure it won't engage." My Goal is just get the Truck Going again and Worry about the Full -AC System in the Summer; Dryer, Orifice Tubes, etc.

Note: I did have the Freon Removed from a local Shop already

Thanks

DSteele41

 

[1998Exp]

Just installing the compressor is a no-brainer -- just a couple of bolts holding it down and a bolt holding the fitting to the back.
It is the other stuff that is problematic...
....
The system contains Freon R134a, which cannot be legally vented to atmosphere, which means that it needs to be suctioned out by a vacuum pump. (Note that a lot of home mechanics wink at this legality and dump to atmosphere... I do not advocate that practice.)
....

Good advice, but just one comment: a vacuum pump is not a recovery system, and it will just suck the refrigerant out to the atmosphere. Investing in a recovery system is not practical for the home mechanic. I would advise to find a friendly radiator/ac shop that will evacuate the system before you work on the compressor and recharge it when you are done. This will keep everything legal, make sure you get the correct charge quantity, and check for leaks. If memory serves, my guy did that for about the cost of an inexpensive vacuum pump that I would otherwise need to buy (he also gave me a set of new o-rings and the oil).