Well, not there yet with the HVAC refresh, but I do finally have the system back together, and drew a vacuum this evening, so we'll see if it holds overnight. I found plenty of confusion on how much oil to add to the system. The service manual says 300ml in 83-522, but if you scroll down, all you see are Delco compressors (so close to Denso! but no cigar). I found a couple places indicating around 8oz is the capacity of Denso 10P compressors, so I went with that. I undershot that by about an ounce since I figured there's probably around that much oil still in the compressor. I'm giving PAO a try, for something different. About the only criticism I could find is that it separates easily from R134, but it's recommended as universally compatible - and R12 carries oil better than R134 (obviously R12 works great with mineral oil, which won't circulate with R134).
I managed to replace all the seals in the compressor without any drama. I even managed to pull the shaft seal from the front so I didn't have to worry about mashing the carbon ring. Here's a good run-down, for anyone who's interested:
. What I did instead of pushing from behind was to grind a little slot just below the tip of the jaws of a needle-nose pliers, and with as much of a gorilla grip as I could muster, I managed to pull it out. I tried with the pliers straight up, but it didn't have enough grip to pull the o-ring past the snap ring land. Before I started, I scrubbed and scrubbed the compressor of probably 36 years and 242,000 miles of grime. That's something I strongly recommend to anyone considering this; nothing worse than crud falling into your (hopefully) pristine innards. The other recommendation is to get everything lined up on a clean workbench so you can step right through the process, limiting the exposure to dust or "oppsies!"
The seal kit comes with some o-rings, crush washers for the bolts, carbon seal, and metal ring that rides on (I think in the video he calls it an extractor ring). Well, it wasn't clear which side was supposed to go against the carbon, and one side had a nick on it, while the original extractor ring looked fine. I guess I have more faith in the original (Denso probably made it to higher tolerances than Santech's offshore bit) even with a new carbon ring, so I cleaned it up and reused it. Time will tell, I guess. Now I just hope my vacuum pump holds out. I turned it on, watched it run a bit, and then went inside for supper to let it do its thing (something I've done before, I think even overnight to draw down as much moisture as possible). When I went back out, it had shut itself off - apparently hit a thermal limited. I turned if off and back on, and it kicked on again. It was at most 80 out in the shop. Well, if it holds a good vacuum overnight, I'll probably just run it another hour and then charge. Still a lot left to do: I pulled the radiator and decided to drain as much coolant as possible and refill, then a few other things under the hood while I'm at it, and finally, all the interior pieces from tearing in for the vacuum pods, expansion valve, and so on. It's a lot of work, but if it were easy, everyone would be doing it!
