Vacuum Source for Heater/AC Hose Octopus?

[andy72]

The 72 Mach 1 I bought has an aftermarket vacuum canister.  It has a Summit gauge on top which reads 25 in when the car is running.

The only vacuum line coming off the canister is going to the power brake booster.

The 351C has a mild cam in it, so I suppose the previous owner was giving the brake booster a nice constant vacuum source.

The vacuum feed line that goes to my Heater A/C octopus is just laying under the hood.

I believe this should go to the vacuum canister.

So, can someone tell me

1.  Does the vacuum feed to my heater controls come off the vacuum canister?

2.  What kind of fitting is on the stock canister?

3.  Does the power brake booster come off the stock vacuum canister?

I may need to add a vacuum fitting to my aftermarket canister if that's where the feed to the octopus needs to go.

Thanks

 

[Danno]

I have a 72 sports roof with a plain jane 302 2bbl.

All my heater/a/c vacuum pressure (oxymoron? LOL) originate from the canister, and go to the control and then to the octopus maze behind the dash to their respective pods

Mine are just slide on connections., and my canister appears to be original .

I have manual brakes, so I don't know about the booster setup.

I am saying this from memory, so I hope i'm correct. Have not looked behind the dash in a while.

 

[Danno]

I have a 72 sports roof with a plain jane 302 2bbl.

All my heater/a/c originate from the canister, and go to the control and then to the octopus maze behind the dash to their respective pods

Mine are just slide on connections., and my canister appears to be original .

I have manual brakes, so I don't know about the booster setup.

I am saying this from memory, so I hope i'm correct. Have not looked behind the dash in a while.

 

[Don C]

Yes, the heater/a.c. controls run off the vacuum canister.

The stock canister has two nipples on it, one with a one-way valve that goes to the vacuum tree on the manifold, the other to the control switch.

The brake booster connects directly to the intake manifold.

Pictures in this threads should help:

https://www.7173mustangs.com/thread-vac-can-mystery-help?highlight=Vapor+canister

 

[andy72]

Thank you Danno and DonC.

I had never seen the stock vacuum canister before in it's original application.

My 66's and 67's didn't have them. It's used only for the feed to the heater controls.

I suppose I'll put the power brake booster back on manifold vacuum like my 1st 67, and use the vacuum canister only for the heater/AC controls.

Thanks Don for mentioning the one way valve. Don't think I would have thought of that. (never dealt with a vacuum canister)

 

[eddyw]

maybe this can help:

 

[rocket366]

Yea I'm using an aftermarket vacuum canister that is the size and shape of a softball for the heat/ac with a check valve

so it works with engine off. The power brake booster gets it's vacuum from the manifold/or/ carb fitting and the check valve

is integrated into the fitting on the booster. The engine has a pretty wild cam but no issues with having enough vacuum for

the brakes.

I guess the term wild for a cam is relative.

Paul

 

[andy72]

maybe this can help:

Very Nice schematic! Thanks