Thank you all for your advice. Now, here’s the latest: After David mentioned the possibility of the water valve not opening, I took a look at the water valve before setting out on a drive earlier today. Thanks to David, I may have found the solution, but with a new problem, though very minor, I hope. When I looked at the thin rubber hose which fits over the narrow top of the heater valve, I found the hose had somehow become twisted, perhaps due to age or when installed at some point by a previous unscrupulous individual. The twist may have formed over time, I don’t know. At any rate, I carefully separated the hose from the narrow tube, smoothed it out, then fitted over the tube once again. I carefully massaged the section where the crimp had been, hoping there would be enough room for a suitable quantity of suction to be generated. Then, I started up the car and went for a five mile drive. Temperature was warmer today than Sunday when I drove it last time, the air a bit drier. I’d say it was definitely a warm day with temperature in the mid 80’s F. . To my delight, it felt as though the a/c was definitely significantly colder than a few days ago, not as bitingly cold as a modern day Toyota, but definitely cold. The auxiliary fan did not come on, but with my 82 degree C thermostat in place, temperature gauge was still half a notch below 90,. Now, here’s where the aggravation set in. After I returned home, I massaged the thin hose again, hoping to make sure it wasn’t completely blocking a proper vacuum. Suddenly, the formerly crimped section developed a tear, much to my dismay even though the other sections remained intact. I tried to follow the hose to see where it leads, but it ends up in a morass of other hoses against the bulk head, and I wouldn’t want to risk getting in there and causing more havoc unless some of you tell me it’s easier to change than it appears. When I removed the end of the hose from the top of the orifice of the water valve, I was pleased to hear and feel a slight ‘whoosh’ of vacuum being released, so at least I think the valve is in order. My question now is this: I’d rather not dig into where the rest of the undamaged hose goes, so would an auto supply store possibly have a short section of a solid narrower piece to which I could slide two sections of rubber hose on to , then connect to the water valve, avoiding the search to find where the rest of the hose leads to, and thereby manage to restore vacuum to the water valve? Any and all thoughts appreciated. Thanks
Mel R