Vacuum actuators

[GTSpecial39]

I am trying to find what they are actually called and where to find the "vacuum actuators for the heater that opens and closes the flaps for the floor heater and defrost. All I have now is defrost and am trying to figure out how to fix it. The slides all seem to work on the control panel but all I get is the defrost. Any help would really be appreciated. Thanks

 

[Hemikiller]

The default failure position for the AC system is defrost. Before replacing any parts, you need to verify that there is vacuum going to the control head in the dash. No vacuum, nothing will work. You should be able to hear the system doing *something* if there is vacuum present.

 

[Aus73Mach1]

There is a great article on this site on testing all the operation of the vac actuators (motors). Mine was a complete mess, all pulled apart, hoses off, etc.
Steps I took to resolve and fix it as per spec.
It helps if you can supply some external vac source plugged into the manifold vac line otherwise you will be running the engine all the time trying to sort it out.
First, test each actuator separately to ensure it is operating, I think one is 2 stage. The diaphragms in these can fail being so old. One of these leaking can make testing difficult to isolate other issues.
The air control assembly can also be leaking, check that as well.
Original coloured hoses are great if you still have them all, I didn't so the diagrams are essential to see where they all connect.
Vacuum should be held with the engine off and vac motors will work for a short time until the vac canister is depleted. The vacuum canister check valve could be at fault or leaks elsewhere. If so a simple solution is to put a small one way valve in the line. Only a couple of dollars and you don't need to replace/rebuild the vac canister.
I hope this helps and I've probably missed a few things. I may still have diagrams, photos, etc of the heater box and where everything goes, many from this site.

 

[Aus73Mach1]

Here's that article, thanks to member who supplied it.

 

[Bobby]

I am trying to find what they are actually called and where to find the "vacuum actuators for the heater that opens and closes the flaps for the floor heater and defrost. All I have now is defrost and am trying to figure out how to fix it. The slides all seem to work on the control panel but all I get is the defrost. Any help would really be appreciated. Thanks

Do an internet search for vacuum motors. eBay is an excellent resource for classic car parts.

 

[Bobby]

I am trying to find what they are actually called and where to find the "vacuum actuators for the heater that opens and closes the flaps for the floor heater and defrost. All I have now is defrost and am trying to figure out how to fix it. The slides all seem to work on the control panel but all I get is the defrost. Any help would really be appreciated. Thanks

Also consider buying the old shop manuals if you do not plan on any heavy modifications.

https://www.ebay.com/itm/126711208246

 

[GTSpecial39]

Thanks for the info. Will do some checking!! Alos, very nice car, I think we have twins almost!!!!...lol

https://www.ebay.com/itm/126711208246

 

[GTSpecial39]

Thanks for the info, planning on getting at it as soon as O get it back from the paint shop. Not sure if it makes a difference, but I did take the air conditioner off when I rebuilt the motor

.The default failure position for the AC system is defrost. Before replacing any parts, you need to verify that there is vacuum going to the control head in the dash. No vacuum, nothing will work. You should be able to hear the system doing *something* if there is vacuum present.

View attachment 94979

There is a great article on this site on testing all the operation of the vac actuators (motors). Mine was a complete mess, all pulled apart, hoses off, etc.
Steps I took to resolve and fix it as per spec.
It helps if you can supply some external vac source plugged into the manifold vac line otherwise you will be running the engine all the time trying to sort it out.
First, test each actuator separately to ensure it is operating, I think one is 2 stage. The diaphragms in these can fail being so old. One of these leaking can make testing difficult to isolate other issues.
The air control assembly can also be leaking, check that as well.
Original coloured hoses are great if you still have them all, I didn't so the diagrams are essential to see where they all connect.
Vacuum should be held with the engine off and vac motors will work for a short time until the vac canister is depleted. The vacuum canister check valve could be at fault or leaks elsewhere. If so a simple solution is to put a small one way valve in the line. Only a couple of dollars and you don't need to replace/rebuild the vac canister.
I hope this helps and I've probably missed a few things. I may still have diagrams, photos, etc of the heater box and where everything goes, many from this site.

 

[GTSpecial39]

Thanks for the info, I just want the floor heater to work along with the defrost. I removed the air conditioner when I rebuilt the motor.

There is a great article on this site on testing all the operation of the vac actuators (motors). Mine was a complete mess, all pulled apart, hoses off, etc.
Steps I took to resolve and fix it as per spec.
It helps if you can supply some external vac source plugged into the manifold vac line otherwise you will be running the engine all the time trying to sort it out.
First, test each actuator separately to ensure it is operating, I think one is 2 stage. The diaphragms in these can fail being so old. One of these leaking can make testing difficult to isolate other issues.
The air control assembly can also be leaking, check that as well.
Original coloured hoses are great if you still have them all, I didn't so the diagrams are essential to see where they all connect.
Vacuum should be held with the engine off and vac motors will work for a short time until the vac canister is depleted. The vacuum canister check valve could be at fault or leaks elsewhere. If so a simple solution is to put a small one way valve in the line. Only a couple of dollars and you don't need to replace/rebuild the vac canister.
I hope this helps and I've probably missed a few things. I may still have diagrams, photos, etc of the heater box and where everything goes, many from this site.