Vacuum Canister

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Blmeis

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1973 Mustang Convertible 351C "Q"
View attachment IMG_20160122_130127555.jpg[attachment=36855]So after looking over other post for an hour I decided to just ask. Reference the picture. You see the vacuum canister and I think its called the carbon canister? The black vacuum canister has 2 hoses. 1 goes into firewall while the other is just hanging off canister. The blue canister has a hose that goes to fuel tank I believe. Looks like a port for another hose is on top but no hose connection. I'm looking for information on these to ensure they get hooked up properly. That's if they need to be hooked up?
 
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So after looking over other post for an hour I decided to just ask. Reference the picture. You see the vacuum canister and I think its called the carbon canister? The black vacuum canister has 2 hoses. 1 goes into firewall while the other is just hanging off canister. The blue canister has a hose that goes to fuel tank I believe. Looks like a port for another hose is on top but no hose connection. I'm looking for information on these to ensure they get hooked up properly. That's if they need to be hooked up?
Going from memory here.

The black canister is actually a vacuum amplifier or stabilizer. One hose goes to manifold vacuum and the other connects to the vent control switch in the interior after passing through the center grommet in the firewall.

The blue canister connects to the hose going back to the tank and has a larger wrapped foil hose that connects to the air cleaner. Then the cleaner creates a flow of air toward the intake from the fuel vapor hose coming from the tank.

Let me know how wrong I am on that one.

kcmash

 
Hi,

Black small canister is for the heater box moving the pots(see pic)

Blue canister is recycling fuel gas from fuel tank and is sucked up into the air cleaner(missing or not connected hose is going to the air cleaner)

eddyw

 
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Right on KC. The vacuum canister is a reserve tank usually with a one way valve so it holds a reserve when the dash pots move and need a volume of vacuum.

Sent from my SM-N900W8 using Tapatalk

 
Thanks! Based on my zero knowledge of this it seems to make sense. I haven't yet to find a vacuum diagram that includes these two items though. Also not running a stock air cleaner so don't think the blue canister can be hooked up properly unless I find a hose that fits both can and air cleaner.

 
The easy-to-find vacuum diagrams are for the emission systems. The charcoal canister is covered in either the Ford engine manual (volume 2, sections 21 & 24) or emission manual (volume 6), depending on year. The a/c vacuum system is covered in section 36 of the Ford Shop Manual and some versions of the wiring and vacuum diagrams manual.

 
Here is picture of original car you can see the vapor hose going into the air cleaner box. You should have places for fittings under the bottom of most aftermarket air cleaners for PCV and vapor returns. You have to knock out the plug and get the correct elbow to hook up. You really need the PCV to keep moisture out of your engine and the vapor hookup does not hurt your performance and takes care of the vapors.

David

DSC00152.JPG

 
Here is picture of original car you can see the vapor hose going into the air cleaner box. You should have places for fittings under the bottom of most aftermarket air cleaners for PCV and vapor returns. You have to knock out the plug and get the correct elbow to hook up. You really need the PCV to keep moisture out of your engine and the vapor hookup does not hurt your performance and takes care of the vapors.

David
David, that's great information! Thank you!!

 
Here is picture of original car you can see the vapor hose going into the air cleaner box. You should have places for fittings under the bottom of most aftermarket air cleaners for PCV and vapor returns. You have to knock out the plug and get the correct elbow to hook up. You really need the PCV to keep moisture out of your engine and the vapor hookup does not hurt your performance and takes care of the vapors.

David
David, that's great information! Thank you!!
Just to help clarify, the connection to the air cleaner would be for the breather, not the pcv valve. The pcv valve should be connected to a full manifold vacuum source which is typically found at the carb base plate.

 
Does anybody have any info or pictures on how to connect the blue canister when you have an aftermarket air cleaner?

Sorry, I just saw on the previous post about knocking out a plug underneath

 
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Just to add to the great info already here, the charcoal canister was part of the early Fed. emissions requirements, instead of the fuel tank venting or admitting air via the filler cap, it vented through the charcoal canister. This canister should in turn be vented into the air cleaner so any excess fuel vapor doesn't reach the atmosphere, it gets inhaled by the engine. If that other port isn't hooked to anything, it's possible that fuel vapor could leak out underhood, which is why others have suggested to route it into the air cleaner if possible...

 
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My aftermarket air cleaner just had one port in the base for a hose connection. I used a short piece of hose to a tee and then ran one side to the canister and the other to the breather on the valve cover.

 
Thanks for all the great info guys!

 
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