Quick A/C flush question.....Jrichker or anyone else

[Black1987Stang]

I'm putting a/c back in my car after a few years of not having it, I had taken the lines off 2-3 years ago when I did my motor swap and I left the lines off the evaporator unplugged and want to clean it out in case any dirt, dust got in there...I had rinsed it out with a garden hose and steam cleaner and blew it out with compressed air to get the big stuff (was my only idea before I bought the flush solvent), now I want to get the remainder and get it dry in there....How can I rinse it out? I bought a can of ac flush from advance so I just pour it in the top line and let it run out the bottom and run compressed air to the top one till just air comes out the bottom? .....I'll have a vacuum pump soon but I have all new lines, dryer, condensor and dont want to contaminate them with the junk from the evap by sucking down a vacuum in the complete system....sooo I just need to clean out the evaporator alone, should I just use that flush and compressed air?
thanks

 

[backfocus]

A good simple way is to use a flush gun such as the one below.

You can use Mineral Spirits or a commercial flush solvent.

Spray it in one end and hold a rag over the other, this helps create some pressure to force out any particles, letting the rag loose after a few sprays. Do this a couple of times then switch sides and flush the other direction. An lastly if you have access to some Nitrogen, you can do a final flush with that to help remove any left over flushing agent.

Since you are using something that you are pouring you could pour a little in then, use nitrogen to force it out the other side. You could use air, but only if it is filter dried. I don't like putting anymore moisture into a system than I have to and that is what will happen if you use unfiltered compressor air.

Also don't take the caps off the new dryer until you are about to install in, just 10 minutes of it exposed to the air can render one useless.

 

[jrichker]

Backfocus's advice is excellent. Follow it if at all possible.

Water is death to A/C systems , so I hope that you got all the water out. Flush the system with mineral spirits with some 91% alcohol added to remove any last traces of moisture.

The Ford systems use a orfice tube in place of an expansion valve or capillary tube. It resides in the high pressure feed line that comes from the condenser up front of the radiator and connects to the evaporator in the passenger compartment. It is not replaceable, so if it clogs, you replace the high pressure feed line. Some models may have the orfice tube in the inlet to the evaporator core.

My current vacuum pump is a refrigerator hermetic unit (motor & compressor in one unit). It was a freebe from a local used appliance store. I bolted it down to a piece of plywood & soldered a 1/4" flare fitting on the suction line. It works great, pulls 29" of vacuum in about 10 minutes or less. I have used it several times and have had excellent results.

See the link in my sign for R134 conversion and A/C charge instructions.