North American Turbocoupe Organization

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The connection I had for free a/c service has closed down so I am now looking at buying a vaccum pump to suck down the a/c system. I located one at www.northerntools.com but it's $290. Any body know someone who might sell them cheeper?

Thanks James
There is an old trick, not EPA approved...scroll down to the homemade vacuum pump description.

Disclaimer/disclaimer/disclaimer: REFERENCE USE ONLY do not attempt to actually construct a low cost homemade vacuum pump even though they work fine.

http://www.biopatent.com/ac.html
harbor freight has them for $10. I know of sveral people useing them to vac down there system.
I made one for free out of a fridge air compressor. It pulls 27" and makes zero noise at all, uses very little electricity, and doesn't get hot.

I got the plans from www.turbomustangs.com in the tech articles. Basically all you do is chop it out of the fridge A/C system but leave the two lines connected. Lots of refrigerant oil will spew out. Wire up the pump to work and ground it. Plug it in and you will find that one line sucks and the other blows. Hook it up and run some A/C lube through it every once in a while. Enjoy your awesome vacuum pump. I used it on my A/C and it worked great. I hooked it up using a cheapo $15 rig of barbed fittings, a vacuum gauge, and an R134A retrofit kit/manual fill valve (on/off) to actually connect it to the system.

Real easy, real cheap and it gets the job done just as good as a shop pump.
I have been using the same compressor from a fridge for the last 30 years..Solder a fitting on the suction side for the hose to fit and put a short pigtail on the power to the comp and your in...
The compressor I used came from a mini fridge, and the power plug was already wired up.. as for the suction tube, I just clamped a length of plastic tubing ($5 / roll from Home Depot) with a clamp.
Any one have pics of these non-buildable homemade good working devices? I need to build one so I can recharge my car's A/C. Also what other parts do you need to fit the schrader valves? And which one do you hook it to, hi press side/lo press side; which is which??

Jim B Big Grin .
If you have an air compressor that can deliver 90-100 psi for a few minutes, the harbor freight device is (IMO) the easiest.

That said, since reading the above, I'll be looking for discarded fridges now......

(Which will just add even more crap to the house/garage/shop, wooohooo.)
To anybody that uses that Harbor Freight device, what is the max vacuum you have pulled with it. I can only get about 22 on mine.
I have the REALLY cheap harbor freight one that doesn't even have a gauge on it the $9 one, but it can bottom out my a/c gauge vaccum range. I think it's 30 inches? Is the 22 inches able to by held by the system?

If your vacuum pump simply only does 22 inches then that's not so bad, just compensate by leaving it pumping longer to get all the moisture out. If you have a smaller compressor and can't hold it very long, ramp it up to max vacuum and shut off the hoses and every 10 minutes or so vacuum it again. The whole point is to evaporate the water out of any left over air in the system.
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