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Fuel vapor separator
Does anyone know what the foam type material is inside the fuel vapor separator that sits atop the fuel tank? I have found that if I install the unit without the foam when walking up to the car you can notice a petrol smell around the car. The other unit with the foam (and cleaned up since taking that photo) basically no petrol smell is noticeable. Both cars roughly had 3/4 to a full tank of fuel. The "foam" must be soaking up the fumes. Wondering what it is and maybe a substitute can be used? Maybe made of charcoal like the canister in the engine bay?

Apparently these were used on Ford cars produced 1971-1972 I'm assuming 73 also but they are not a reproduced part. I've had a look around and they seem to be in the "unobtainable" category!

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Should be a closed system. Are you sure that the O ring between the two is good? Seems like one is not providing a good seal. Just my thoughts.

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I agree with John, the lack of a mesh in the vapor connection should not contribute to the smell of fuel. I would start with the gas cap gasket, then check the gasket between the vapor vent and tank and the hose from the vent to the hard line. Check the hard line for rusted through places. Make sure the vent hose is connected to the charcoal canister and the canister is connected to the air cleaner. The charcoal granules in the canister will loose their effectiveness over time. It's possible to replace them with fish tank filter charcoal granules.

I don't think the material in the vapor vent is anything special, just something to slow down the slosh inside the tank from getting into the vent hose. I would use some stainless steel steel wool as a replacement.

“If you can't explain it simply, you don't understand it well enough.”
--Albert Einstein
I did clean the other separator before installing it. I managed to find another rubber ring to replace the original. I cleaned up the "rusty" metal washer/ring also. The foam piece is only about the size of the center hole. When I cleaned it out about a tablespoon of dust with a strong petrol smell fell out it.

I am using petrol caps specifically for the 71-73 Mustang (Scott Drake). Brand new fuel lines. I did wonder about using stainless steel wool as a replacement - will give that a try. I'm wondering if the charcoal canister is the culprit will swap over and see (smell) what happens.
My suggestion is along the lines of what Don and John suggested....swap gas caps and see if the smell follows the cap.
Are you sure you don't have a rust hole in the tank just above the seam?? A tiny pinhole can cause the same odors you are experiencing especially where the tank is above 1/2 full... JMHO

The person who says it cannot be done should not interrupt the person doing it. 

My fuel vapor separator assembly did not have the material like that is pictured. The Ford part number is D1AZ-9B328-A. +1 with the other responses.

mustang7173;278518 Wrote:asusnz,

My fuel vapor separator assembly did not have the material like that is pictured. The Ford part number is D1AZ-9B328-A. +1 with the other responses.


mustang7173 there was a very early version of the housing that was more open inside with no filter material. There must have been an issue as it was changed.
If your housing looked like his in the picture - it had the foam when it was new

I agree with the other guys no filter won't cause the odor
Switching the caps would be the easiest test.
Next might be a new O ring and metal lock ring. They are the same ones used on the sending units and fairly cheap.

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if the cap doesn't work inspect the vapor lines themselves, they get clogged and rot out.
Im bringing back this thread, im also searching for the mesh material in the separator. Mine is still there, but the material is falling aparts, and these little granules falls in the fuel tank.
So anybody knows which material it is ?
Otherwise i may use stainless steel wool as Don said, if i can find it somewhere.
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