Rebuilding the ac/heater control switch

[3175375]

I believe I did drill too far. Lesson learned. I have an NOS a/c heater control and removed a heater control off a parts car I have and bench tested with the actuators on the floor of the car. I checked all the lines with a vacuum pump and all are holding air and moving and holding correctly. with both units the actuators extend on DEF mode and retract on OFF. The shorter shaft actuator retracts on HEAT mode however no, or little air through the floor vents. I rebuilt the air box some time ago and all was cleaned and lubed (if possible, can't remember). The flaps, I am sure could only be installed one way so don't think that's the issue. I only have vacuum lines for two actuators so I think all that is correct. Is there something I am missing or should be trying? The red stripe vacuum lines are on the shaft side from what I read in above post from Detmatt however a different system. Its a non/ac 68' 300.

I believe you are correct. Look at the video posted earlier, to verify.
You would need a tee to operate both the heater/defrost and a/c actuators as there’s a linkage between the two of them.
You should be able to physically see that.

 

[3175375]

I had ordered an NOS recirculating/fresh air actuator, 2936018 and have installed it. The actuator I replaced worked, but didn’t appear to be as strong as the one I installed.

Verified that it works.
I had to attach the clip blind and there’s a spring that keeps the door either in recirculating or fresh positions.

NOS actuator installed:

Old actuator:

Next is to install an NOS AC/heat actuator, install mode/temperature control switch and verify all actuator operations.

 

[3175375]

Retested all 3 of the actuators. Fresh/recirculate was sluggish/appeared to be non-operational.
Since I had ordered a mode selection switch from Jegs, I decided to drop it in and the fresh air/recirculate actuator now operates rock solid.
The ac/heater actuator that I ‘rebuilt’ was also not regularly moving to my liking and I could get it to work by twisting the actuating rod a bit.
I have an NOS ac/heater actuator coming from Blue Star Performance and I will swap it in upon arrival. I also will rebuild the questionable ac/heater actuator as the diaphragm was good when I disassembled it, and I have some ideas on how to correct the problem as well as an idea on how to make the actuators serviceable.

Defrost actuator is good, but I have an NOS defrost actuator on the shelf.

Bottom line is that I have had to replace:
- recirculate/fresh air actuator
- mode control switch
- ac/heater actuator

and
- re-plumb the time delay relay and engine vacuum circuits

In addition to these things, I had to:

- swap the suction and discharge hoses to the compressor (Mis-plumbed during ‘restoration’)
- install a new expansion valve (defective-maybe from running the system backwards)
- install a new receiver/drier (good measure)
- evacuate and recharge the R-12

This all has been done to a car that was ‘completely restored’.

I am blessed to have the capability and enough brains to be able to get these things solved.

The air conditioning, heater and defrost function great now.

I should have Shamu out on the road next week in time to take my fiancé and give my Mom a ride in it for her 85th birthday (with the top down)…

Absolutely worth the frustration and effort!

 

[3175375]

Verified installation of all 3 actuators and mode control switch. Here’s a video of all 3 operating:



Next steps are:

1) secure all wiring, hoses
2) install glovebox
3) install front trim
4) install dash trim
5) verify dash lighting and indicators
6) verify and top off refrigerant
7) test drive 8^)

 

[Fury Man Van]

Great Job I bet you can't wait to get her out on the road.

 

[3175375]

Got everything assembled and no dash lights. Cobbled together a hacked dimmer rheostat, ordered a replacement and will do a shakedown on Monday.
HVAC is done.

Next ‘restoration’ cobbled mess is the backup lights and swap the dimmer switch upon arrival.