AC charging ? Re: vacuum pump

[Methodical]

I did some research on charging the AC unit. I want to evacuate the system but don't want to spend $200 and up for the evacuation pump. So I checked on Ebay and they have these Venturi type vacuum (Air Vacuum Pump AC Conditioner Evacuation) ofr about $30 shipped. It requires that it be hooked to an air compressor, which I have and the compressor has plenty compacityto handle.
1. Has anyone used a Venturi type vacuum?
2. What are your thoughts on this item?

Thanks

 

[clarkjr]

I have used one and it did work fine. Drew down to whatever the spec called for but the compressor had to run the entire time (33 gal 5 HP). You could try it or do what I did the second time and find a shop that will draw a vac for you.

 

[jrichker]

The vacuum pump powered by compressed air are not really good enough to do a proper job of vacuuming down an air conditioning system. You need to be able to pull 28.5" or more of vacuum for about 30-45 minutes to do the job right.

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.

 

[Methodical]

Thanks

 

[89 Saleen#455]

Try calling some pawn shops in your area.

http://www.pawnshops.net/state_page.php?stateid=MD

I've picked up 2 Robinair vacuums over the years at pawn shops. Paid $27.00 for the first unit and $70.00 for the second unit (the thing was brand new).

 

[PuterAmI]

I gave you an answer somewhere else. Even a link to the Robinair unit mentioned above that you can buy for $50 new.

 

[Methodical]

I gave you an answer somewhere else. Even a link to the Robinair unit mentioned above that you can buy for $50 new.

Yes you did and I ordered the Robinair yesterday. Just waiting for delivery. Thanks. Hope it works.

 

[TC93]

You could do it the old shade tree mechanic way,,,,,,,,,, make a fitting so that you can hook it to a vacum source on the motor and let the motor vacum it down. (I don't recommend it, but it has been done.) Doubt it will pull enough vacum unless you have a stock cam ,, and then it might.

 

[PuterAmI]

Thanks. Hope it works.

It works well from my gauges. You will be pleased.

 

[Methodical]

It works well from my gauges. You will be pleased.

Update:

PuterAmI, GREAT CALL. If I ever see you a 6 pack is on me . I used the Robinaire Air Vac and it worked flawlessly. It actually pull 29.7 within 2 minutes. You can see it just pulling vacuum. I ran the pump for five minutes or so and check to see if the system held the vacuum; it held. Then I ran the vacuum for over 1 hour then began charging. I flooded the system on the high side with 1 can of liquid charge. It sucked that can dry so fast, which I assume means the vacuum was strong.

So for you DIYers take it from me, you can get the Robinaire Air Vac ($50 + $8 shipping) and know that you can get the job done with ease. You don't need those $200 and up pumps. Now, I can't speak on behalf of daily heavy usage (i.e. repair shops) of this pump but DIYers - go for it. Now, I am freezing my ass off.

Note:

1. I have a 30 gallon 150PSI compressor which didn't break a sweat doing the job. I also used the 134a manifold gauge. For those who don't have the gauges, get them. Using only the low side charge hose tells you nothing of what's going on it the system ($ well spent).

2. Do not use those black/blueish colored O-rings that Ford sells. They are too small (Besides the ones in the system are green). Go to Autozone and get the Green O-rings - pack with 4 of each size go for $4. Also, if you have to replace the highside AC service port (both of mine were leaking) it already comes with the Green O-Ring installed (so save yourself some $). Uhmm, funny Ford installs the Green O-ring on its valve but sells the black/blueish ones over the counter

3. AC Service Port Valves PN for future reference: talk them down on the price to $10

Low = F3AZ19E762A $15.82
High = F3AZ19E762B $13.95

Again, Much Thanks Puter.