A couple of years ago I got a recommendation from a friend for a good repair shop that is close to where I live. I have had them do a few repairs on my vans and they have also worked on my son's Camry. I have been happy with their work and what they charge. A bonus for me is that the owner has a genuine appreciation for Toyota vans. I developed enough faith in them that I took my 87 4WD in at the beginning of last summer to see if they could resurrect the AC. They put in a rebuilt compressor, recharged the system and I had working AC for far less $ than I expected.
When the weather finally warmed up here recently in the PNW, I switched on the front AC and got warm, not cold, air out of the vents. I took the van back to the shop and was told that the rebuilt compressor (from O'Reillys) was no longer doing the job. I haven't had much luck with rebuilt stuff from the auto parts stores in recent years, so I wasn't too surprised. I offered to get a "new" rebuilt for them to put in and purchased a Denso from Rock Auto. While I was awaiting its arrival I switched on the rear AC while driving and found that I was getting cold air out the back. That made me question their diagnosis but the new compressor was already on the way. I had them install it when it arrived and the front AC still didn't blow cold. The current explanation for the problem is a stuck heater valve. The owner of the shop didn't charge me for the work they did and said he would install a heater valve for free if I could find one.
My questions are: Is a stuck heater valve a good explanation for the symptoms? Since heater valves don't seem to be available for these vans, what are my options for getting my front AC to work. Could I bypass the valve so I can have AC (but, presumably, no heat) for the warm part of the year? Has anyone been able to find a heater valve for another vehicle that they were able to make work on their van?