1961 Continental AC Cutting Out & Follow Up

Bill –
I have a 1961 Lincoln Continental that has developed a strange AC issue this spring. When I start the car and let it idle the AC is just fine — cold, strong fan, no problems. As soon as I put the car in Drive, the AC goes off completely. We’ve done extensive checking of the vacuum lines and have replaced any with leaks or potential leaks. Someone suggested checking the “basketball” in the right front fender, and another Lincoln buddy thinks it might be the conduit plate in the steering wheel that is connected to the gear indicator and actuates the door locks when the car is put in Drive.
Any thoughts? Do you all carry that conduit plate?
Dave
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Hello Dave –
The AC controls on the 61-2 are well known to have these kinds of problems at some point in time so I am not surprised that you are experiencing some issues. Many of these issues are indeed caused by vacuum leaks.
When you state that the AC goes off completely when you select drive, I can’t tell if it goes off when you accelerate in drive, or are idling in drive. I also can’t tell if the air gets warm, or if the blower stops also. In any case your statements do sound like loss of vacuum of some sort in the AC/Heater control system. Vacuum can be lost from a leak or leaks at any area where the vacuum is routed. Popular vacuum leak areas for your car are……the main control switch, the vacuum reservoir, system check valve, any vacuum servo or at any vacuum line, etc. One way for you to diagnose for or confirm a vacuum leak would be to “T” in a vacuum test gauge to the vacuum line that supplies the main AC/Heater switch and then start the engine while watching the gauge reading and observing the AC properly operating nicely while idling in neutral. At this time select drive and as the AC “cuts out” as usual, observe the gauge for a significant vacuum drop. If the gauge indicates a drop in vacuum when the AC “quits” then you need to test individual components in order to find and pinpoint that leak or leaks. A vacuum diagram and testing skills are usually needed to avoid guessing and replacing parts that are not defective.
The door locks do not automatically actuate when drive is selected on a 1961 Lincoln as your friend suggests. However we do carry in stock or have easy access to most of the parts to repair your 1961 Lincoln.
By the way Dave, do you currently have a parts account with us at this time?
Sincerely,
Bill
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Bill,
Thanks so much for this information. We will proceed following your guidance. In response to your questions, the AC goes off when I put the car in drive as a rule; however, last weekend, I put it in drive and it kept running until I began to accelerate, then it shut down. It seems to me that the blower just stops when the ac goes off.
We will go through the vacuum checks (again), and follow your guidance. If we need any parts, I’ll be in touch with you. I don’t think I have an account with you, but I think I have bought some parts from you for my 1960 Lincoln some years back. Appreciate your time and great guidance!
Dave