AC questions

[All-American]

Hi everybody,
I feel like the AC us running well in my 73 New Yorker. It has Auto Temp II. I have had it charged and the mechanic that filled it couldn't find any leaks. After installing the 1amp fuse that finally came in the mail yesterday I am left with a mostly working, pretty cold air system with 2 questions.

The vacuum controlled door behind the glove box only seems to be going to 20% and either 100% closed or open, I'm not sure which is which based on my service manual. Does anyone have an idea why it is not going through all 3 positions like the manual says it should?

2nd question... I get good air out of the holes under the dash by my feet, especially on drivers side, but my defrost seems a little weak and my middle dash vent and the 2 vents by the doors are basically not working?

Please advise and as always thank you for the help.

All-American

 

[CBODY67]

The air flow out of the under-dash "holes" does tend to be biased toward the driver's side. Same on the heater air flow. I discovered this on our '72 Newport (normal a/c) as my mother was always wanting more heat, but my dad's feet were hot. I fixed that air flow issue by putting a piece of masking tape over the inner 1/2 of the lh floor vent, which put less air on that side and more on the rh side. That equalized the air flow and my mother didn't ask for more heat.

As to the other vent outputs, all of the joints in the plastic ductwork do not have any foam to ensure that air leakage at those joints does not happen. You can find some thin, foam stick-on insulation to put where the joints slide together, or you can duct-tape the joints. Otherwise, the flex-ducts could have deteriorated over time and need to be replaced. There should be one long plastic duct that connects the main unit to the lh side, with a slide vent for the driver's lap area.

I'm glad your system is working well, other than the noted issue.

CBODY67

 

[All-American]

Okay that make sense, of course the drivers side will always be in use so make sure they get the most air. I will experiment with the tape idea.

When I was looking at the ductwork, I had a pretty good idea of what you explained but I am very new to working on cars so I wanted to check with whom I consider the masters.
Thank you for the ideas and explanations.

All-American