Help Please! 67 Cadillac Vacuum Diagram

[Antoni Deighton]

Okay, I've looked through my copy of the '67 Cadillac Shop Manual, and I can't find a copy of the underhood vacuum diagram.

I need to figure out where the other end of the two smaller vacuum lines that lead from the radiator thermostat vacuum control go.

I also need to figure out where the line that leads from the actuator at the base of the distributor goes (I think it's the fitting at the lower left front of the carb.)

Finally, there's a green electrical wire that's taped in the same harness as the yellow wire that attaches to the condenser on the coil. It's got a black quick connect on it, and it seemed to detach from under the distributor when I was removing the coil. The car is fitted with a Pertronix, so I dont' know if this wire is redundant or where it attaches.

Okay, I know I should have labeled them, but I didn't plan on removing them. In fact I don't even remember removing them, and I'm drawing a blank with the manual. I was replacing the rocker cover gaskets since they were leaking so I only planned to remove the minimum, and those details aren't covered in the manual!

If anyone can let me know where those four things attach, that would be great. Otherwise a suitable page reference in the shop manual would be a big help too!

Thanks for your help.

Antoni

[Antoni Deighton]

It seems that the dark green electrical wire connects to the "thermogage" temperature sensor. The manual describes how to test it, but does not describe it's location. Now that i think i know what it is I'll keep looking!

Still not sure about the vacuum lines from the vacuum distribution switch/block in the radiator. Any thoughts?

Thanks,

A.

[Antoni Deighton]

Okay, I (think) I've found the connector for the temp sensor. It's a brass "nub" bolted into the head at the front left of the engine, and the connector seems to slide across it. It's quite loose, so no wonder it came off!

I've found a description of the vacuum plumbing from the TVS (thermo vacuum switch in the top of the radiator) in the manual (page 6-82), but so far it's not proving helpful!

[Antoni Deighton]

Well, it looks like my TVS (Thermo Vacuum Switch) has been bypassed, with the manifold vacuum line capped, and the other two disconnected. The distributor line was plugged straight into the carb. That's all fine and it obviously works. Now I know how the lines should be routed, I can make the change later.

BUT, it raises another question.

My TVS is a four port switch, but from what I've read they originally they only had three ports. The fourth port is connected to a vacuum line that fits into the air filter cover. So my question is, is the air filter cover original and was this a common period modification? What does this do, and should I try to find a three port switch so that I can bring the car back to original?

Thanks in advance for your inputs!

A.

[Glen]

It sounds like your TVS is a generic replacement.  I would look for a correct TVS.  The ports are marked as M, C, D; for Manifold, Carburetor,  and Distributor.