'73 Cuda 340 with A/C - vacuum question for owners.

[CudaDownUnder]

Hi all,

I have a '73 Cuda, 340/727 with A/C. The previous owner removed a few items and never put them back in so I'm trying to find out how it should be.

The direction of air flow through heater box is controlled by "air doors" that are moved by a vacuum actuator. I need to find out where the source of the vacuum comes from. I am certain that it comes from the intake manifold but I cannot determine where.

If you have a 72-74 Cuda with a 340 (or other small block) and A/C can you please look under your hood and trace the thin rubber hose that enters the engine bay through the firewall, just to the right of the blower motor and see where it goes to. I would be greatful if you could take photo and post it.

I should also mention that my car has the California Smog gear fitted that feeds off the intake manifold as well.

Thanks in advance, Ed.

[71FJ6]

I don't know if this will help but I have a 71 383 with air and there is fitting behind the carb that screws into the intake manifold that goes to the brake booster and it has a small tube that the vac.hose attaches to.I have a 72 Road Runner that has the same set up but the small vac line operates the air grabber hood.

[CudaDownUnder]

Hi 71FJ6,

Are you saying that there is a small nipple on the brake booster where the large hose from the intake manifold goes in? If so, I have that nipple.

[Mopar73340]

If you have power brakes ther is a fitting that is screwed into the intake behind the carb that the 3/8 vacuum line going to the brake booster hooks to and there should be a small nipple comming off the side of this same fitting that is used for the vacuum for the a/c heater controls. If not you can use the one at the brake booster but you will need and adapter to go from the larger hose. I can get you a pic of the fitting if necessary.

[CudaDownUnder]

Thanks Mopar73340,

I'm sure that I can organise an adapter if need be.

If it's not too much trouble, I would appreciate the photo.

Ed.

[Mopar73340]

Ed, see attached pic of the vacuum fitting. The small hose on the back goes to the vacuum operated Heater / A/C controls. This fitting is behind the carb on the intake runner to #8 cylinder.

[CudaDownUnder]

Mopar73340,

Thankyou, Thankyou, Thankyou.