Yes it's simple, just follow the directions.
But, since you asked, here's how it works.

First and foremost wear safety glasses.
As easy as the conversion is I'm paranoid about blowing a hose. A coworker of mine has a blown ac hose on his desk and I'm always hearing about how his mechanic blew it up (with R12). Fortunately I haven't had the same problem.

The kit (from InterDynamics) includes a filling hose with a valve on one end and a quick release chuck on the other,  three cans of combination charge, oil and stop leak and adapter valves. You screw these adapters on over the existing valves as part of the conversion. This prevents mixing up R12 and R134 down the road. These valves are like tire valves only a tad larger. On my 91 I only changed the one on the back of the compressor. I couldn't find the other one and was too lazy to really look for it. I suspect it's up in the ceiling somewere. (Anyone know?)

Before you put the adapter(s) on determine if your system is empty. If your compressor clutch doesn't engage when you turn on the AC it's probably empty. (The clutch should kick in by itself when you charge it up). To make sure it's empty use a Phillps screwdriver or similar implement  to depress the pin on the valve at the back of the compressor (with the engine and ac running). If nothing comes out it's empty. If it does then you'll have to take it to a shop so it can be sucked out. If it's not empty please don't empty it into our atmosphere, thank you. But we're van people..we'd never do that.

To charge the system start the engine, put the ac on full blast. Now screw the end of the hose with the valve onto one of the cans and turn the valve handle CW all the way to pierce the can. At the other end, pull back the sleeve of the QC chuck and slide it over the newly installed adapter on the valve at the rear of the compressor. Push and release the sleeve. Tug on it to make sure it's secure. Turn the valve on the can fully CCW to release the charge. Hold the can upside down and shake it vigorously. (At this point I envision my friend's hose blowing up so I stand with my body on the opposite side of the van side-wall). You'll feel the can get lighter and colder. When it feels empty pull back the sleeve on the QC connector to release. A little hissing from the can/hose may result. If it continues for more than a few seconds it's not empty. Reattach it and continue. If necesary you can shut the valve on the can to stop it's discharging.  Repeat with the two additional cans. Now go feel the ice cold air blowing from the vents. Ahhhhh!

If you want they also sell a reasonalby priced tire valve style pressure gauge to double check your system pressure. I bought it but only used it the first time.

That's it. Good luck.

Disclaimer: Please be careful, don't get hurt. If you don't have the confidence don't do it just cause I said it was easy.

Thomas Brobst
Accu-Sort Systems, Inc
Staff Mechanical Engineer
215-721-5061
fax 215-799-1600

If we knew what it was we were doing, it would not be called research, would it? -Albert Einstein 

>>> "Samuel L. Walters" <samuel.walters@verizon.net> 7/1/03 >>>
Thomas,

I have seen the same kit at my local Advance Auto, but had not bought it 
yet.  When I get the suspension fixed on my Syncro and a new accelerator 
cable in, making it derivable again, AC is high on my list.  

Is the kit simple, as in just follow the directions?  Does it require 
any special tools, etc.?  Perhaps you could write up a short "here is 
how to do it" and post it to the list.  Many of us have the same 
situation and can get this kit easily.

Thanks,

Sam

-- 
Samuel L. Walters
Attorney at Law
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