1980 HVAC Control Assembly Rebuild

[packagerjr]

My '80 Bronco's HVAC control head is out of the truck for a once-over.  It lacks any real detent feel at each vent position.  Vacuum testing the switch shows the switch to hold vacuum when it should, but that some positions (especially on the heat side) are kind of finnicky in terms of when they'll port vacuum out and when they won't.  I'd like to fix that, if possible, while it is on the bench.

Mr. Gary Lewis, I see you have taken these switches apart and successfully cleaned them back up to restore functionality per this thread.  Can you describe the process just a bit, and is it terribly difficult?  I am of decent aptitude, but these switches appear to be hard to come by, so I don't want to tear mine up or have a million parts jump out when I release the spring nut.

Thanks,

Mike

[Gary Lewis]

Mike - It has been a number of years, and since I turn 72 tomorrow I think I can legitimately claim that my rememberer used to work better, but I'm not sure as I don't remember.

But if I remember correctly, inside there was just a sliding valve that lined up with a lot of passages, depending on the position.  And by cleaning the old grease out and using new grease I was able to get some "feel" back in it.  I think it was held together with melted plastic that came through the removable piece, and I cut those off smooth and drilled them to accept very small sheet metal screws and washer to reassemble it.

[packagerjr]

Thanks Gary.  No problem on the rememberer, mine has a few less miles but rest assured does no better.

If I get into mine I’ll take some pictures and share them.  It appears Ford changed the unit in 83? so it reduces the availability of a replacement.  I’ll likely still give it a go, or perhaps but a donor from the junkyard and practice there.

Thanks again!

[1986F150Six]

Is this it?

https://www.ebay.com/itm/NOS-80-FORD-TRUCK-BRONCO-HEATER-CONTORLS-E0TZ-18549-A-FoMoCo/273876172535?hash=item3fc44abef7:g:ZicAAOSwsXpc9tO-:sc:USPSPriority!95125!US!-1

[packagerjr]

No.  Mine has factory AC and has the rear windows switch for the Bronco.  The vacuum selector valve 19B919 is what I want to clean up and have it function.  I haven’t been able to find a 19B919 for sale and the entire modules are expensive and unlikely to be in any better shape than mine.

Pic is from a junkyard truck but mine is the same minus the fuel tank switch.  Sorry lousy formatting, need to read the picture post.

[1986F150Six]

Like this?

https://www.ebay.com/itm/VINTAGE-FORD-BRONCO-A-C-CLIMATE-CONTROL-WITH-BACK-WINDOW-SWITCH-1980-1981-1982/163709929754?hash=item261ddf491a:g:YF8AAOSwxJ9c7SYS:sc:USPSPriority!95125!US!-1

[packagerjr]

That’s it.  I’ve previously seen one for $150 but this one is a bit cheaper.  The “tested works well” is a bit too generic for my taste, but may be as good as it gets for a 40 year old item.  
Thanks for the eBay links, provides a nice backup plan.

[1986F150Six]

Still searching... this came up, but I have not found Motorcraft YH361?

https://www.stockwiseauto.com/motorcraft-yh361-hvac-heater-control-switch?Year=1980&Make=Ford&Model=F-100

[packagerjr]

Got it apart - will post pics later.  Was completely different than I expected.

Anyway, the vacuum directing piece is a rubber disc that looks like a maze.  Rotating it exposes various tiny vacuum ports.  Anybody know an appropriate grease to apply to the ridges on the disc?  Dielectric came to mind but open to suggestions.  I found a vacuum grease that plays nice with rubber and plastics but it was $144 a tube!

[ArdWrknTrk]

Dow Corning makes lots of silicone and flourine based greases that can get quite expensive.
But when they are talking about vacuum, they are talking about close to absolute vacuum, like in a scanning electron microscope...

Regular Super Lube (in the silver tube) or any of the O-ring specific greases like I get at the lumberyard to rebuild my nail guns should be fine.

You may be able to find a little $1 envelope of O-ring grease at your local auto parts by the register. Along with the antiseize and threadlocker.

[packagerjr]

Thanks Jim.  We have plenty of o-ring grease st work and that would work good.  May give that a try and see if I can help the disc slide without gumming up the whole shooting match.