FUN! I'm rewiring my 90 Civic DX for AC right now! I blew a fuse and tin-foiled it, then fried my thermostat and some wires! I've been replacing parts and rewiring all weekend and am getting ready to put it all back together. Right now I'm driving around with no dash...it looks very messy.
Dax: I take it your having to rewire the 90, because it keeps burning up chewing gum wrapper's. They have a pretty high current tolerance. Sometimes they allow you to find the problem, by using the sniff technique, because the wires get so hot the insulation is melting off.
Have you finished sorting out what was causing the problem/
I have the parts to retrofit A/C into my 89 Wagovan, so presuming I get the 87 going, I'll be working on it. After having removed the parts, for both, I think that the extra couple of inches they added in 88 must have been to make it so that a real person could reach their hand in to work on something on the A/C. On the 87 everything is in the way of everything else. Very exasperating.
Yes I figured out the problem. Last summer my main relay had been giving me cranking issues. In the hot summer, the joints expand and the connection becomes erratic, causing poor starts. Instead of springing for the $40 for a new one, I figured I'd open it up and reflow the joints with solder, since they are prone to failue due to cracked solder joints. I guess I did it wrong, because after doing this, I blew my condenser fan fuse (under-hood fuse panel, 15A).
I was pissed because it was a very hot day and I wanted my AC (this was actually last summer). I went in the house and got some tin foil and wrapped the fuse then put it back. The AC worked GREAT for about 15 seconds, aside from that charred electric smell. After that it quit working. I replaced the main relay with a new one and all my troubles went away...except my AC was still broken.
So now I've replaced nearly all the electronics and run lots of new wires. I think the thing that took the biggest hit was the thermostat, which is embedded in the evaporator, so I just put a whole new evaporator in this past weekend.
Dax: When you replace the O'rings, you should be able to get O'rings which are built with nitrate, which allows them to hold in the gas. I bought a collection from a Napa auto part store. The O'rings I got are a light green, although I have also seen them in light blue. I've had the counter guy's at some places try to sell generic O'rings, as replacement's, but those will blead off the charge.
On recharging, you can get it recharged with R134, or you can get it recharged with a replacement for R12. If you get actual R12, it is extremely expensive, since theoretically they aren't making it anymore.
HOWEVER, you can also use a refrigerant called RedTek 12a. This refrigerant does not require a refrigeration license. It's cooling qualities are similar or better than R12 and it takes less refrigerant to charge a system. You can order it on the Internet for $7/can, plus shipping. It takes about 4 cans to recharge a system from empty.
Also, if you've had the system open for more than 24 hours or so, you will probably need to put a new "filter/dryer" into the car. It's a silver can, about the size of a spray can. It's probably on the driver's side of the car, near the compressor. It has two lines which go into it, from the A/C system. If it's been open for very long, the dryer get's saturated and if you try to recharge the system, it will just freeze up, when you run it and not work. Then you have to discharge the system, put a new one in and start over.