Hello, I am new to the forum, and I am trying to figure out the vacuum system for my 1961 Cadillac series 62. The previous owner messed up most of the lines for the vacuum system of the car. I'm trying to figure out where the vacuum system starts from the engine, and how it connects to various components on the car. Including but not limited to the door locks, AC and heater, and brakes. I'm also not entirely sure what else the vacuum system is connected too.
The shop manual has good images of many of the lines. We did question some of the engine side vacuum lines which are not labeled as well in the book.
Here are some photos behind the dash for the lines for the door locks and a valve.
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I'm trying to find the vacuum inlet for everything. There were somethings that have been cut and/or removed, and I'm trying to trace it to the beginning for all of it. Not just for the AC, but from beginning at the motor. From there I'll see what has leaks.
I will add a bunch of pictures and try to talk around them. However I have not had to hook up my own yet.
The vacuum source comes off the carburator and the intake manifold.
The carburator tube goes to a tube and fitting on the top of the brake booster.
The brass fitting on the intake manifold is for accessories and goes to the vacuum tank and others. This fitting is different depending on options.
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Here you can see the booster tube and fitting sticking above the booster.
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The bottom of the booster T fitting goes to an accessory tank in the fender if you have a lot of air options.
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Here is the fitting on the upper tank.
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Here you can see from that fitting, it comes into the distribution valve on the firewall.
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Here you see where a small line comes in from the manifold then to a spliter valve for neutral safety switch and AC controls.
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Here are AC controls.
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This is the best I can do. If you show pictures of what you are working with others may have pointers.
FYI. Soon someone will move your post to the technical section.
Here is how mine is set up. Obviously my carburetor is not like yours. I'm not sure what the cut T line went to. the other side of the T goes to the booster, which then T's off to the accessory tank. The fitting on the manifold goes to the other side of the carburetor, and probably the door locks as shown in the pictures.
You may have a carter carb. But you are missing thd accessory tank above the booster. I beleive that one is always there. And thd one in the fender is only for extra air accessory. Unless I am wrong.
Let me guess, it's supposed to be right here.
Yes. And someone redid your wiring because that convolute is not right.
Okay, the vacuum connector on the manifold, where do the 2 connectors go on your vehicle?
My vehicle is a 2 door, and does not have switches for the door lock.
I am not sure. One may be the dash pot. The other would be the vacuum line that goes into the wire harness bulk head. I believe but not sure.
Vacuum line through firewall at harness Bulk head. I believe this is one.
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Quote from: Clewisiii on July 04, 2025, 09:24:35 PMYou may have a carter carb. But you are missing thd accessory tank above the booster. I beleive that one is always there. And thd one in the fender is only for extra air accessory. Unless I am wrong.
The one above the booster is extra for power door locks and or trunk release.
There is a vacuum line that comes off the manifold and attaches to this piece. What does it activate?
That is ofton called a dash pot and is for throttle vacuum advance.
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I believe that one would be connected to one of the ports on the manifold since it is engine related and not accessory.