I believe I found the source of my air conditioning leak last fall - faulty schrader valve at the low side connection.
I evacuated the system with my vacuum pump and it held fine.

I was expecting to add around 29 oz of refrigerant since it was empty but after at least 20 minutes of filling it (at around 2000 rpm) only about half of my 32 oz can of Dupont Suva 134 got into the system. Looking at my high side and low side gauges, the pressures seem fine as per the ac guide on another thread and the ac is definitely blowing cold.
https://rennlist.com/forums/993-foru...diagnosis.html

Should I try to add more or let it be?

 

Check your temperatures at the vents. If they are good then why mess with it any further?

 

Provide the following:
At idle
low side pressure, high side pressure, air temperature around the outside of the car when you took the readings

And, does the refrigerant can note a gross weight (can plus refrigerant) and can only weight?
You could toss a new can on a scale, weigh it and then compare that to what your can now weighs

 

I believe the pressures were ~12 and ~230 and outside temp was mid 80's at 2000rpm.
I will check at idle tomorrow.
This is the r134a that I used - 35.3oz or 1 kg net weight.

 

Took a run with it today, in 84 degree heat 50% humidity heavy NYC traffic the center vent was blowing about 59 degrees. I was completely comfortable driving around in 0-15mph bumper to bumper traffic for a half hour.

Afterwards I pulled out my gauge set but unfortunately the low side hose on the gauge set sprung a leak because when I opened the valve I got steady hissing. Looks like I'll need to get another hose or another gauge set. This one was interdynamics, might go for a harbor freight unless someone has a recommendation for a hobbyist priced set.

 

With tools, you pretty much get what you pay for.
If you are shopping for a gauge set look for a brand name

 

Yes, same advice I give my kids that if it isn't an emergency don't buy junky tools. I will follow it myself this time.

 

EXCEPT.... when you are only going to use it once!

 

+1 Andy

I have recharged my AC unit twice since 2006.
$15 later all it involved was a can of refrigerant, a hose, and my hand.

• Attach the hose to the upside-down can,
• attach the other end to the low side port on the compressor,
• start the car, puncture the can and open the valve,
• set the AC on high and put my hand over the inside dash vent.
• When my hand gets nice and cold close the can valve and detach the hose from the compressor.

Seems to work well enough. No gauges or gauge manifold involved.
All done in the Wal-Mart parking lot where I purchased the can of refrigerant.
Andy

 

Amazing !
Gotta wonder why there are hundreds of threads by DIY's on Renn and Pelican; models, 911, 924, 928, 944, 964, 968 and 993, never mind the rest of the brands and models, who have tried the same procedure and things did not go as expected.
It must be the Walmart parking lot. Please provide that address so they can all meet you there and you can do that magic.

 

Yes! It's the Wal-Mart parking lot that does the trick, ANY Wal-Mart will do!
OR
They didn't hold the can upside-down?
Or like Arnold, they misidentified their AC compressor as a Snow Cone maker?
I don't know, maybe I'm fantastically lucky, then again how many guys went for a top-end rebuild where all they needed was a proper oil change where overfilling the oil was not in the cards,
I would try the Wal-Mart Jig first though as it may resolve the issue for some at low cost before moving on the more technical and potentially vastly more expensive solutions,
All in good fun,
Andy:-)

 

Yeah, Maybe Costco or SamsClub has better instructions.

 

+1

 

Important to Note: Andy is known to be "cost effective."
I find Andy's explanation credible. The fact that Andy used a can and used the can in a Wal-Mart lot lends credibility to his post.
If Andy posted that he used a set of gauges in Nordstrom's lot, I would find Andy's post not credible. However, since Andy used a can of refrigerant in a Walmart lot, lends credibility to his post.......