[fasst450]

My 72 has factory a/c that most likely needs a charge for starters. The whole system in general is really weak, the reason I say that is that everything seems to function like it should. I can change through max, norm, vent, def, ect and can physically hear the system making changes, the engine RPM's drop when going through the a/c modes. But barely any sort of air comes from the vents in any mode. The blower motor sounds like its ok so I dont think that its just weak but it wouldnt hurt to swap it out for as cheap as they are. I pulled the dash and had a look, I used some heat tape to wrap up some of the duct work where i thought there might be some air leakage going on, but it didnt seem to help much. Do these trucks have any sort of cabin filter? Im almost tempted to pull the trigger on a vintage air but I cant see spending all that money on all that nice stuff with the rest of the truck being mostly original. The triple digits are coming in Texas so I need to "get hot" on this issue. Does anyone have any suggestions on a few things to look into that might be weakening the system?

 

[acauth1]

Yes, keep it original by all means. Do you hear/feel a difference in air flow between max and norm? Also, just because it sounds ok, does not mean the blower motor is not weak.

 

[lsrx101]

Verify that the blower motor is turning in proper direction if it appears to have ever been replaced. I've been bitten by aftermarket blower motors that were miswired internally.

Also, being 40 years old, it's very possible that the evaporator is plugged with dirt and debris thus blocking the airflow. There is no cabin filter and every bit of air ever drawn into the system flowed through the nice wet evaporator.
IIRC, you have to remove the inner fender to access the blower motor. At that point it's not hard to pull the evaporator housing and clean it out. You will be amazed at how much crud is in there.

I agree with acauth1, keep the original system. The POA/TXV system in your car is superior to any aftermarket system today.

 

[LOCKDWN]

Funny that this topic popped up..... I am considering selling the AC unit on my '77 Sprint since I don't have the AC Motor.
The part I have is closest to the firewall.
Let me know if you are interested and what you'll gimme for it.

 

[acauth1]

Verify that the blower motor is turning in proper direction if it appears to have ever been replaced. I've been bitten by aftermarket blower motors that were miswired internally.

Yes, been many many years but have been bitten by that little quark too. That one and motors that have the wrong wheel installed (oppisite direction.)