HI, I am in the process of taking my engine out (1999 subaru outback legacy) and according to my manual removing the a/c is a risk because of high pressure. My question is what is the worst that can happen during a accident with the a/c. I also read that moving the a/c out of the way to remove my engine is possible, but the manual doesn't state wheather i should empty my a/c of gases before moving it out of the way and it does not state which specific connection or valve should I be cautious of.

It is common practice on Subarus to leave all A/C pressure hoses/fittings in place and simply remove the mounting bolts for the compressor and move it aside, typically into the area where the battery is normally mounted. This should give sufficient clearance to remove the engine without disturbing or discharging the A/C system.

 

The hazard with discharging the A/C refrigerant is that it is under enough pressure that it can cause injury to skin, and as it expands and its pressure decreases it becomes cold enough to cause injury due to freezing. In other words, the hazards involve bodily contact with the escaping refrigerant rather than any chemical or fire hazard.

You do not need to discharge the A/C system. Just unbolt the compressor, and unplug the electrical connection(s), then sit the compressor out of the way.

You can do it two ways. One, undo the 12mm bolt that holds the low pressure line to the compressor real slowly until freon starts to come out. Then walk away for awhile, and leave your garage door open. If you are going to do it this way, replace the O-rings on the AC lines going into the compressor or you'll most likely have a leak there if you recharge it. I do it this way if the AC doesn't have much of a charge or is empty because it's a lot quicker. I work on these for a living.

 

I'm now waiting for someone to b itch because it's environmentally unfriendly, hazardous, etc etc. Save your breath, I don't care. Yes, it can harm you, it's a gas under pressure, becareful.

 

Or, you can move the compressor out of the way by removing the 4 bolts that hold the AC bracket in place. You'll need a 14mm swivel socket if you want to make it easier on yourself. Fold the whole setup up over the battery, and use a bungee cord or something similar to hold it out of the way. For a normal size bungee cord, I usually hook one end to the AC bracket and the other end to the coil spring on the driver side suspension, but a towel or something under it so you don't mess up your paint.

Edited February 14, 201115 yr by 94Loyale

dear northwet craig and loyale,

awesome, thanks for the advice.

Move the A/C out of the way as described.

 

As to venting the system into the air, don't. Casual as 94Loyale's comment may be, there is a significant fine for venting your system to the air. You can easily move the compressor out of the way without opening the system.

 

More information can be found here: http://www.epa.gov/ozone/title6/608/608fact.html

Edited February 14, 201115 yr by edrach

true lol

Move the A/C out of the way as described.

 

As to venting the system into the air, don't. Casual as 94Loyale's comment may be, there is a significant fine for venting your system to the air. You can easily move the compressor out of the way without opening the system.

 

More information can be found here: http://www.epa.gov/ozone/title6/608/608fact.html

 

 

aside from the legality of this, you will get a sticky film of compressor oil all over the place, which is quite messy.

Both true statements by Ed and Miles, and very sound advice. My methods are not always legal, I'm a rebel without a cause.