Newby question here!  I've read through the shop manual and as many threads as I could find on here, but I'm still stumped on exactly how to remove the interior plastic Heater/AC box from my 64 SDV in order to replace the mode door vacuum actuator and heater core.  I think I've done everything as indicated, but I can pull so hard on it that it moves my body towards it and it isn't budging.  I don't want to break anything, so any help/photos/advice on what I'm missing would be appreciated.  Here is what I've done:

  • Disconnected all vacuum lines and electrical connections
  • Disconnected the defroster cable
  • Disconnected all vent tubes
  • Completely loosened the huge "hose clamp" on the big rubber seal on the far right that connects to the evaporator
  • Removed the front plastic "distribution box" that connects to the dash vents
  • Under the hood - I have removed speed nuts from 6 studs around the sides and bottom of the housing.  I have also removed the hoses from the heater core.  This is all I have done under the hood - is there anything else required, such as removal of any part of the blower housing, or part where the steamboat switch is located?
  • Finally, I am a bit confused about the floor vent.  The service note 65 (if memory is correct) states removal of two screws that hold it.  I removed 4 that apparently held on that air distribution tube (that's how I got it off), and then after that was off, the only other thing I could find were a screw above and below the left side of the mode door, so I removed these, but it didn't seem to have any impact.  The manual says to pull back the carpet around the lower vent and I have pulled it back a bit to the point where it turns from plastic to metal, but couldn't really see anything down there, perhaps I need to look closer?

When I tug on it, there is a very tiny amount of movement, but the force required to make that happen seems to be approaching reckless and I'm concerned I may break something if I just try to muscle it.  The floor vent assembly is still there, and I'm guessing I've loosened any screws required so it will slip out of there when it's free? Regardless, the amount of pulling force I was using probably would have snapped it off if that was the only thing holding it, so I took a breather and came here for help!  I'm sure there's something I'm overlooking, as everything I've read makes it seem like it should just pull right on out. 

Thanks in advance, and I'm excited to now be a part of this wonderful community!

- Travis

Manteca, CA

Views: 173

Reply to This

Replies to This Discussion

Sure something else needs to be removed based on your description 

Only advice I can give not having done that job yet —but due to do it very soon myself 

A post by - Clovis on here could be very informative regarding restoring the job you are doing if you have not seen that yet 

Stay safe 

My best guess is the blower box should come out under the hood 

Remove the blower box. You will want to change the vacuum motor in there also. Remember, in for a penny, in for a pound.  Dont bother separating the short duct from the blower case to the evap box. 

You may find another bolt or nut holding the inside case in place.

The J shaped heater duct needs to come out. (inside the car) There are 2 screw that go up (vertical) to the  heater box. Pull the carpet back to see the separation joint. There are 2 screws at the edges. 

The big seal on the right wall needs to be cut. Cut out the very aft section, so the duct assembly can be pulled straight back.  You can use black RTV or tape to reseal it.   That duct never just falls out on removal. That happens when you are trying to install it by yourself. 

The studs will hang up, so be cautious and slow.  When installing, do not be tempted to bend the heater core tubes to fit through the fire wall. You will cause a leak. 

Thanks to all for the good advice and explanations. I’m going to get back on it tomorrow and will update with my progress. I’ll remove the blower box and see what all I find. Good idea to replace what I can while I’m in there as this is all a job I’m not eager to do again soon!


 I want to know ( from you or others ) how you will be dealing with the hood hinge that is so very close to the blower motor box area 

I do think the blower box can be removed with the hinge in place but not 100% sure myself 

The manual indicates removal of the hinge  if I am not mistaken 

Removing the hinge ( if needed ) and realigning the hood is not something I am looking forward to doing needing three people to do it right and the possibility of damaging paint 

That answer will help me to get to doing the same job you are now doing as I have all the parts needed for a while now 

Stay Safe 

I’ll try this without good removal and let you know the results! I’ll take a few photos too if there are any tips/tricks I figure out.
Hood* removal ... couldn’t find if it was possible to edit a reply after I saw my typo!

It is possible to edit a reply. Let me see it I can use it here to capture a screenshot.

Yep. Here you go:

You will find that when you do the editing you will be correcting the original thread but the post that goes to the dashboard page will not be changed at all which is a bit odd 

Enjoy and be Safe 

Kurt, is correct. You can edit replies but note you have 15 minutes to do edits. After that you would need to delete and re-post. You can edit a top the main topic discussion post that you created at any time.

Awesome! Thanks guys for the help!

I never remove the hood hinge. If the AC doesnt work, disconnect the AC line from the compressor to get the line out of the way.  Or move the compressor to the right fender. 



  • Add Photos
  • View All


Had to Bring in Some More Help!

Started by Jason Edge in General Discussion. Last reply by Jason Edge 5 hours ago. 3 Replies

As most of you know I just brought in almost 400 lb of Cadmium plated bolts, etc. Cheryl, my boss and Cadillac Parts Apprentice indicated she needed some help when looking at the 1st batch of about…Continue

Headlight Switch

Started by Joseph Rabbene in Restoration Discussion. Last reply by Russ Austin 5 hours ago. 4 Replies

For less than thirty dollars, I ordered a universal '53-'64 headlight switch from   The switch is currently out of stock, but I'd really like to sew up the dashboard on my '63 and…Continue

Classic Cadillac Parts For Sale - Misc Items

Started by Jason Edge in For Sale. Last reply by Jason Edge 7 hours ago. 193 Replies

I have posted a few Misc items over on my Classic Cadillac Parts Facebook page at…Continue

Tags: classic cadillac parts, classiccadillacparts

Needing advice on brake system upgrade

Started by Joe in General Discussion. Last reply by Tony and Ginny 429 9 hours ago. 1 Reply

Has anyone bought from Jamco? If so what did you think of there parts as far as there brake booster and M/C set up combo's.The reason for asking, I own a 62, I know this is a 63/64 site but the…Continue

Blog Posts

Help on Removal of rear seatback on 64 convertible

Posted by Nile Bolen on January 8, 2021 at 11:44am 7 Comments

I'm trying to remove the rear seatback on my 1964 deville conv.  The only help on this site that I can find is the following:

The seatback, its bright stainless trim, and the speaker grille are removed as an assembly.  The seat back hangs on two hooks near the top, and is retained to the body by two bolts and washers near the floor, one on the right side, one on the left.Once these fasteners are removed, lift the seat back upward and free it from the hooks

I've removed…


Bumper lower bucket

Posted by Ray Schick on January 1, 2021 at 4:33pm 3 Comments

1964 Convertible Seats.

Posted by michael moorman on November 30, 2020 at 5:29pm 1 Comment

Are the front and rear seat frames the same for 63/64 Coupes and Convertibles because Original parts group  makes reproduction seat covers for 1963 only and and i prefer the 1963 seat pattern so with that being said does anyone have information regarding this thanks.

Picture of ignition switch

Posted by Cees de Bunje on November 27, 2020 at 6:20am 0 Comments

Does anyone have a close-up picture of the ignitionswitch with keys in it made in landscape format? Switch must be in dashboard. Many thanks in advance. Cees.


  • Add Videos
  • View All

© 2021   Created by Jason Edge.   Powered by

Badges  |  Report an Issue  |  Terms of Service