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

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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. 



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