Gas filling tube/ tubes

[ISG]

Hi,


Wanted to ask.
The largest tube obviously is the one that fills the tank with fuel (you put a gas pistol in it)
The rubber hose is the hose that comes from Charcoal Canister.


Question number one is that is the very small diameter steel tube that goes along with the filling tube? What is the purpose of it?
Question number two is: Is there some kind of valve at the end of that rubber hose witch comes from the Charcoal Canister up to the filling neck? Or is it just ending without nothing? Then the valve should be in the Charcoal Canister itself?
I need to know witch one of those hoses/tubes actually lets fuel tank to breathe while I'm filling.
In my old car there was a solenoid that was opened during filling, so the gas tank could breathe, and was closed when driving, so the fumes were kept inside the system. How it works in the cougar?


Thanks,

 

[Relliott6879]

I would imagine the smaller of the two tubes is a breather tube.

 

[ISG]

If it is a breather and is always open, what is the point on the rubber hose that comes from Charcoal Canister? Also this would mean that fuel tank always breathes though it.

 

[Relliott6879]

I'm afraid I have no idea!

 

[Quicksilver]

Do you have an extra heater system installed as there isn't a 'charcoal canister' or 'rubber tube' on the parts diagram?:

http://eucatparts.com/?action=cat_ford_part&s_id_part=22734&s_id_model=90

The tank vents through the smaller metal pipe.

 

[ISG]

Maybe its because this is a fuel system diagram. Charcoal canister and rubber tubes are on ALL vehicles from 70'. Maybe they are listed on other diagrams. Charcoal canister is a box beneath a spare wheel, and there are 2 rubber hoses, 1 from the tank to canister, and another from the canister to filling neck.

 

[spjmorris]

number 9 in this one Andy, our cats have them it's just forward of the subframe from memory
http://eucatparts.com/?action=cat_ford_part&s_id_part=22735&s_id_model=90

 

[Mako]

If it is a breather and is always open, what is the point on the rubber hose that comes from Charcoal Canister? Also this would mean that fuel tank always breathes though it.

It definitely doesn't vent to atmosphere constantly - it wouldn't be allowed and in any case you can feel the pressure when you open the fuel cap. As Andy (and Rich!) said, the thinner pipe on the filler is the breather, but it vents behind the filler cap.

I also have a vague recollection (possibly wrong) that it also forms part of the anti-syphon?

I've never had a need to mess with the charcoal canister but from the diagram Steve posted it clearly has an In and and Out, so is also sealed.

 

[Relliott6879]

Wow, I got something vaguely mechanical vaguely right!

 

[banhim]

It definitely doesn't vent to atmosphere constantly - it wouldn't be allowed and in any case you can feel the pressure when you open the fuel cap. As Andy (and Rich!) said, the thinner pipe on the filler is the breather, but it vents behind the filler cap.

I also have a vague recollection (possibly wrong) that it also forms part of the anti-syphon?

I've never had a need to mess with the charcoal canister but from the diagram Steve posted it clearly has an In and and Out, so is also sealed.

Anti-siphon isn't usually that grand, ones I've seen are generally some sort of physical obstruction in the filler neck rather than a clever pneumatic device. Can't say with total certainty on a Cougar however. Try sticking a bit of hose down the filler neck of your car and see how far you can advance it if you want to find out?

The pipe being described is almost certainly the tank breather and rightly it shouldn't vent to atmosphere!

 

[bobster1982]

its a breather for when you are filling the tank