Cadillac & LaSalle Club Discussion Forum

Cadillac & LaSalle Club Forums => Technical / Authenticity => Topic started by: Cadillac George on March 29, 2024, 01:34:52 PM

Title: Vacuum part
Post by: Cadillac George on March 29, 2024, 01:34:52 PM
Hi, can anyone tell me how to remove this unit and where to purchase it.  It's on my 1966 coupe.  Looks like someone pried it opened!
Title: Re: Vacuum part
Post by: Cadillac George on March 29, 2024, 01:36:30 PM
Hi, this picture did not open up in my last post.  Sorry about that, don't know why it didn't transfer. 
Title: Re: Vacuum part
Post by: TJ Hopland on March 29, 2024, 06:44:11 PM
Looks like it was one of the vacuum operated servos that operates one of the doors in the ductwork.

Why would someone pry one open like that?  Did it spring a leak so they opened it to jam it in the operated position?  Like maybe it defaults to AC and they wanted it to heat without actually thinking about it too hard or actually fixing anything?
Title: Re: Vacuum part
Post by: Cadillac George on March 31, 2024, 07:50:31 PM
Thanks for the reply.  Any ideas on how to remove it and where to purchase it.  I think I need to go under dash but not sure.  Any suggestions would be appreciated. 
Title: Re: Vacuum part
Post by: Clewisiii on March 31, 2024, 07:52:56 PM
You probably need to remove the airbox. There should be bolts on the back.
Title: Re: Vacuum part
Post by: cadillactim on April 04, 2024, 11:38:44 PM
That is the mode door actuator, sends air out the dash vents.

Remove the six bolts that hold the box to the firewall on the engine compartment side. Disconnect power servo and heater core hoses. Pull air box away, it will clear the engine. Not that difficult.

You can get replacement actuators from Old Air Products in Texas.

Tim
Title: Re: Vacuum part
Post by: badpoints on April 05, 2024, 01:59:07 PM
Thought a picture of my 67 would help but they look surprisingly different. IMG_0632.jpg
Title: Re: Vacuum part
Post by: CadillacFanBob on April 05, 2024, 03:35:14 PM
1974 Cadillac master parts book lists:

Group #9.280 Vacuum Element, heater Inlet part #1998916 fits some other model years also from 1959 thru 1974.

Google is your friend with this part number found NOS on e-Bay.

Bob