69 air condition

[Klaus Friedrich #33362]

Hello NCRS members,

I'm doing the next step on the restauration of my 69 convertible. I'm exchanging the dashbord wiring harness - the fusebox included. No problems ;-)

Now I have a question:
Not able to start the car now, what is the best way to test the vacuum valves of the air condition?
Am I right if I speak of three valves? Outside air (in the right door pillar), air up and down (near to steering column) and a third one in the plenum (can't see the valve - only the door)?

Greetings from Germany
Klaus Friedrich #33362

[lyndon Sharpton]

Re: 69 air condition

If you can pick up a mityvac vacuum pump, you should be able to test with it. I know that eastwood has them.

[Jack H.]

The easiest way is with a 'mule' car....

Park your daily driver car/truck outside the garage. Connect a LONG hose to its vacuum nipple on the intake manifold. Run the hose into your garage and SHUT the door.

Now, connect the outside vacuum source to the pickup hose that used to connect to your car's intake manifold. You'll be able to exercise ALL of the car's vacuum functions in the silence of your garage WITHOUT the engine running and verify functionality PLUS be able to hear leaks in the system!!!!

About the only function you really can't exercise without the electrical system be operable is the wiper door since it's actuated by an electro-vacuum relay mounted on the back of your instrument cluster tachometer that's fed electrical power from the WSW switch....

Using an electric or manual vac pump has a few drawbacks. First, an electric pump makes noise which obscures the sound of system leaks. A manual pump doesn't have much reserve capacity making it tough for you to exercise this/that vac component and actually walk around the car looking and listening. Last, you have to pay $$$ for the pump when a donor car/truck is FREE!