Maybe a dumb question? Climate control 1971

[Guest Gee_Rydes]

Hello

I have a 71 Riv with Climate control. I also have a dash with wiring harness for a regular AC system. Can the control heads simply be swapped or is there much more to this system that would also have to be changed out.

Thanks for any advice and sorry if this is a dumb question

Dave

[NTX5467]

You'd need to swap the complete hvac control system, not just the control heads. It might be that the basic case is the same, but I somewhat suspect they might not be the same. While the regular a/c control will have direct-acting levers (or cables) to control the blower motor speeds and a rotary vacuum switch to open and close the mode doors in the unit to vary the temperature and where the air output comes out, the automatic system has a "programmer" that does all of that in a very sophisticated manner, doing things the normal system is not capable of doing.

Now, generally, everything "fits in the same hole", but what fits in the hole is unique to the respective complete system in its complete form.

What might be wrong with the existing system? Just curious.

Enjoy!

NTX5467

[Guest Gee_Rydes]

Thanks for the quick reply.

The vacuum dispersement wheel does not seem to direct vacuum to the correct places. I have had it out and verified that the vacuum does not correspond to what the manual says for the various modes.

Most of the air is directed to the lower ports at this time. I bypassed the controller and applied vaccum to the lines that should ope up the various mode doors and that seems to work correctly. I do not have cold air, but it is cooler air than outside which leads me to believe that it may only need a recharge to become cold again. The bigger problem is the modes not directing air to the correct place.

Hope this makes sense and thanks for your help in advance.

Dave

[NTX5467]

On the normal systems, when the vacuum source to the vacuum reservoir goes away, the "default" setting is floor and defroster air with the controls being unresponsive to get it to change to the desired locations. At least, that's how the more recent systems operate.

As the workings of the system depend upon a solid and steady vacuum source, you might start by tracing the vacuum supply line from its source (either from the check valve on the power brake booster or tee-ing into a vacuum distribution tree somewhere under the hood. A vacuum line might have split with age, for example. As the vacuum line is a smaller size, a leak there will not usually cause a major change in idle quality or performance while driving. In addition to checking the vacuum lines, you can't fully rule out the vacuum reservoir itself from possibly having a leak. Be sure that the replacement vacuum line stock you might get is pretty thick-wall hose rather than the thinner stuff designed for the same ID spec.

The a/c coolness could well be a freon charge issue, but for the inside controls to work as designed, the vacuum source needs to be what it needs to be.

Just some thoughts,

NTX5467

[Guest Gee_Rydes]

Thanks for your advice. I can tell you that I removed the vacuum harness from the rear of the controller and I do have 2 source lines that hae vacuum. I joined one of those lines with the correct color coded line to make the upper ducts operate and they did. I would think that would rule out a vacuum source problem and also whether the diaphram at the door worked, but I could be wrong. That is what led me back to the controller.