QuestionDear Dick; I have this nice old bomb that pumps out heat all the time, no matter where the temp lever is positioned. I looked at where the lever cable runs and it moves ok and pivots what looks like a valve under the passenger side of the dash. Under the hood, to the right of the a/c firewall unit is a hose that is connected to 2 fittings right next to each other. I'm wondering if this is correct. THe a/c compressor clutch engages and it blows hot, too. I don't think there's any freon in it. The fan doesn't blow very forcefully, either. There aren't many of these old monsters around to compare with. Also, at around 25mph, i get a squeal that almost sounds like air blowing over a bottle. If I get on the highway, it seems to disappear and isn't as loud at lower speeds, but it's annoying. It doean't seem to increase in frequency as the car gains speed, but it jumps... almost in harmonic frequencies. I thought it was coming from the back end of the car, but I've replaced the left side rear wheel bearing. The other corners look ok when i replaced the shoes... it did it before that too. Don't know. Thanks for any help that you can be.
AnswerFirst, be sure to unplug the wire that goes to the AC clutch so that you don't burn out the compressor by running it with no Freon in it. Those are tough old compressors, but they can't stand being run with no Freon, because the Freon is what circulates the lubricant to the compressor internal parts (bearings, piston rings etc.). The wire to unplug comes out of the front edge of the compressor, toward the center of the engine, and has a place to unplug it right next to the upper radiator hose. It is very dark in color (I'm color blind, so I'm not sure if it is black or really dark violet or blue) and it is the only wire that goes to the front of the compressor with a connector in it.
The heater hoses should pass through a water valve which is operated by a vacuum hose that comes from your dash control system. It sounds like the water valve has failed in the open position, so it will roast you out unless you replace it or disconnect and block off the hoses. If you follow the heater hose that comes from the top front right side of the engine, you'll come to the water valve about 2/3 of the way down the right side of the engine. If you feel the water hoses when the engine is running and warmed up, and if the valve is stuck open, the hose going into the control valve will be the same temperature as the one coming out of the valve.
To trouble shoot this car further, you are going to need a copy of the Factory Shop Manual. If you go on the Imperial club web site, which is www.imperialclub.com, and search through their literature, there is a shop manual posted that you can look at or print out pages from.
The heater fan doesn't go all the way to high speed unless the driver is calling for MAX DEF or MAX AC. When you get the AC working you can try that again, and if the fan still won't go to high speed, the fuse for the high speed blower winding may be blown, or else the switch might not be working right. Again, this is a very complicated car, and you cannot troubleshoot it without a manual to guide you.
The noise you are hearing could be any of a hundred things - and I can't see how to sort them out without knowing what part of the car is making the noise. If it sounds like wind over a bottle, it could be a poorly closed window on the car, or a missing weatherstrip. These cars should be perfectly quiet on the road (I know, I drive a 67, which is almost identical mechanically, although the AC and the body is different from yours).
The way to track down a bad wheel bearing noise is to put all the windows down, go to a big empty parking lot, and weave around with the car to see if it is coming from the front or rear of the car, and if it gets louder on a right turn than on a left turn, or vice-versa. If the noise increases, the side you are turning AWAY from is the side with the bad bearing.
Good luck with the car. Those were the best driving luxury cars of the 60s - a real treat on the road!
Dick
