64 AC : Blower runs, air is felt at firewall, but not through heater outlets or AC vents (HEAT/AC door WORKS)

[Norman Silverman]

Hello All.

As I am getting in to this troubleshooting with the benefit of Tim Groves invaluable book, I find something that is not covered; blower works strongly but no air can be felt either at heat ducts or AC ducts even though the Heat/AC mode door DOES WORK when I apply vacuum to the solenoid that controls it. (thanks to Tony and Ginny 429 for clueing me in to what panel to remove to observe the door). 

As luck would have it, I have buddies who own a MOPAR junkyard and one time they took in a 64 CDV with AC. So I managed to get some parts off of it to practice on and to use. I got what turned out to be a good Transducer and installed it, so now when I run the temp wheel the Power arm moves from AC to heat and changes the blower speed. HOWEVER, nothing comes out of anywhere even though I can hear the blower working hard AND I can feel a STRONG rush of air all the way in the back near the firewall. I had thought what I was feeling was the INTAKE for the blower with the RECIRC door stuck open (solenoid inop), but now I am not so sure. 

When I stick my hand inside the heat/ac blend door I can feel that something is flowing, but not alot; it sounds/feels like there's lots of air moving, but not in the right direction. 

Stumped!

All replies welcome, thanks.

Norm

[Norman Silverman]

Noted and already done. I replaced the Transducer and it does respond accordingly (low vacuum=AC, high vacuum=heat). QUESTIONS: MUST I remove the hood hinge in order to remove the Heater Box Cover? Also, can I remove the blower duct under the hood going from the blower to the plenum without removing the hear box? AND, will that let me see in to both the Evaporator and the heater core? 

Thanks

[3n49omug8n28i]

Remove the inner right fender panel. The hinge doesn't need to be removed. I cant remember for sure but I dont think you can see the evaporator only the heater core is visible.  The evaporator needs to be pulled out the view it 

[Norman Silverman]

OK, NO WAY I can pull the inner fender panel, it is also where the hood hinge is anchored, so I have to deal with that no matter what. Anyway, I stuck my camera inside the big square duct in the lower kick panel and the side of the heater core I can see is beautiful and clean. YES, I know it is the other side I need to look at, but there isn't even a trace of dirt/leaves/grease, etc on the outbound side, so that's encouraging. Then, I loosened up the blower duct under the hood and stuck my camera down to the bottom; nothing in there. I am going to try to turn the cable to face the inlet side of the heater core, just in case it is blocked up. I then turned on the system, pried open the duct a bit and felt a strong breeze from the blower: so much for my silly theory of reverse direction-it is blowing the right way. 

Then, I stuck my hand all the way in to the ac recirc chamber and noted that rather than the air coming from the recirc channel back to the blower, it is coming from the area where the recirc door opens. This can't be right because there's nothing to enclose that air to make it go to the proper duct. At least now I have a hint as to what I need to try to examine next. 

More as I do it. 

Thanks!!

[Norman Silverman]

Clovis. OK, NOW I see what you are referring to; a skinny strip of metal that's more like an inspection plate that allows full access to the left and the lower area of the blower plenum, which allows observation of the Heater Core (or Evaporator-not sure). 

Thanks

[3n49omug8n28i]

Great I'm happy that you found it. It makes removing the outside heater and a/c plenum soooo much easier. You may be able to inspect the evaporator without removing the refrigerant lines and definitely be able to inspect the heater core. Just something to check off your list as possible problems with the system. I installed a new blower motor with new seals on everything to make it nice and airtight. If I remember correctly it was a vdo blower from rock auto. It had the venting hole the same as mine. Some dont have this hole. Be sure to check yours if you decide to replace it. It was very cheap to purchase. A little rubber elbow goes from the blower motor to the plenum. If your rubber is missing or rotted then you could also purchase the sealed unit.

The evaporator is bolted in separately from the plenum but you may be able to slide it back to inspect it. The evaporator drain is likely trash also so I made one out of a piece of bicycle tube and glued it flat. I forgot to order it with other parts from rubber the right way. It will keep out drafts, bugs, mice and dust. 

[3n49omug8n28i]

Ok I just reviewed my picture of the evaporator. It's in it's own case and it needs to be fully removed to open it. Good thing you have the camera to look in and see it without removing the whole nine yards. Once the outside plenum is removed you will be able to get your camera in there and inspect it without removing the evaporator and case. I think I'm going to get one of those when they come on sale. 

[Norman Silverman]

Available at Harbor Freight for less than $100. Very well worth it!

[Norman Silverman]

"STUDNICK'S" !!!!!

I haven't thought about them since I lived where the salsa in that commercial comes from: New York City.

I grew up in Brooklyn (BTHS'64) and then lived in Queens after I got married. We always used Studnick for certain machine shop functions that nobody else did quite the same. 

Next you're going to tell me you shopped at Leslie Edelman's for ammo.

[3n49omug8n28i]

Norm, are you looking at the small removable panel that's located to the rear of the front inner fender? Or the inner fender itself? If you look in the front wheel well towards the rear of the car there is a removable panel for accessing the antenna and comfort control system. The whole inner fender stays in place along with the hood hinge. I'm sorry I'm not sure I'm explaining it correctly. Removing this small panel makes it very easy. 

[Norman Silverman]

Clovis: That makes A BIG DIFFERENCE! Thanks!

That's quite a project you undertook! I've never done anything near as complex, and now there's no way I could (too many aches and pains). Thanks for sharing !

Norm

[3n49omug8n28i]

this is the only picture I can find that shows the inner fender panel removed. I did remove the hood hinge because of some major updates at the time. 

[3n49omug8n28i]

this was my evaporator