Gas Fumes

[ron69912t]

Ever since I have owned my 69 ther is an odor of gas fumes in the garage. There are no gas leaks anywhere!

The gas tank is vented into the Venelation Container, P/N 901.201.062.22 and out through plastic hose to the front of the car and out the bottom of the front pan.

My Venelation Container is empty..should it be filled with activated charcoal to absorb the gas fumes? I know US cars use charcoal gas tank venelation filters.

The Venelation Container sits up under the left side of the dashboard inside the trunk.

What is inside yours??

Thanks,

Ron D

[craign]

Ron,

I have the gas trap in the same location yours does, however the overfill tube runs back in to the container (large loop on top). Mine is just and empty container, no charcoal or filter media to speak of.

When I first got my 69 my garage stunk of gas to no end. A carb tune and sync (weber 40's) cleared it right up.

Craig

[adot]

I thought thats normal with all old cars. Oil, gasy smell. My wife hates it, but I love it. Must be that Tim Allen? thing, men are pigs.
Brett

[ron69912t]

Craig/Brett:
Have brand new Webers on my car, no gas leaks there. The smell comes from the gas tank vent tube under the front pan.

Strange that they would place an empty container in the gas tank vent circuit. My guess is that the Venilation Container contained an odor absorbant of some kind. There is no referance to any filter media in the Porsche Factory Parts Manual just the container.

I plan to get some activated charcoal and fill up the container with it. Will put in brass screens so it does not get into the gas tank.

Or just get an activated charcoal filter from the junk yard and retro fit it to my car. The stuff lasts forever.

Thanks,
Ron D

[craign]

Ron,

Does this vent tube run out the center of the front, kind of in front of the spare tire?? I thought that might be a water drain hole or something but now I wonder if mine is plumbed incorrectly.

Craig

[ron69912t]

Craig:
Thats a good question. I will trace the hoses tonight and report back tomorrow.

The plastic hose sticking out the left nose pan goes up over the gas tank toward the venilation container area.

Ron

[craign]

Ron,

Is this what yours looks like?

[cgarr]

My guess would be that the plastic box should be empty and is only positioned there to vent the tank and prevent a syphon of the fuel when the tank is topped off. If you only had a vent tube, even up as high as the box you could still get a syphon should the tube become full of fuel, the air in the box breaks the syphon effect. You could still get some fuel thur the vent as I do but I can still fill the tank up to the cap without any leakage.

Just a guess!

Craig

[ron69912t]

Craig:
That is exactly what mine looks like. You may be right on its function. Maybe someone else can verify it's prupose too.

Sounds logical.

Ron

[craign]

That explanation sounds as plausable as any. I can't imagine putting a tank that might fill with gas over all those electrical relays.

I have never seen a drop of anything in it in the year I have owned the car, since my "firewall" disintigrated I have clear access to it and have kept an eye on it.

I have supposedly found one of those "firewalls" in perfect condition and have been promised twice that "it will ship tomorow". I am still waiting and holding my breath. I am also talking to a guy who restores antique aircraft that might be able to help me mfg one of the "Ron Specials" out of aluminum. I saved the mounting brackets from my old one.

Craig

[ron69912t]

Craig/Cgarr:
I checked the hose path last night. A 3/4" hose goes from the top of the gas tank to the large inlet on the Venelation Container. A smaller 3/8" hose comes out of the VC down toward the front of the car. Its path is under the gas tank filler piping.

I felt something under the metal gas filler tube rubber hose connectin sleeve that connect the metal gas tank pipe to the metal filler pipe. Not sure if it is a hose clamp or the "T" connector as shown in the Parts Manual, I can't see behind the pipe and can get only one finger in there. This T does not connect to anything in the drawing. So the question is why is it there? Vented to air would fill the trunk up with gas fumes.

The hose then goes down around the spare tire and out thru the hole & grommet in the front pan. It sticks out under the car about 2-1/2". I put my finger in the hose end and it came out wet with gas yet there is no dripping on the floor under the hose.

It has been in the 90's here in Chicago and my car is always covered, even in the garage, so the garage is very hot which causes the gas in the tank to evaporate more. The car cover collects the fumes and concentrates them they don't just wiff away to the garage roof. So when I walk by I get a wiff of this heavy concentration.

Last winter when I had the car in storage and covered I would get a very heavy smell of gas inside the car when I uncovered it to check it. Kept the mice out for sure.

Wonder when driving if there is a suction created on the hose end which draws out any gas fumes from the gas tank?

I plan to put in a cannister of Activated Charcoal just before the tube goes out the front pan. I'll let you know how it works out.

Thanks,
Ron

[craign]

Here is the pic I am looking at, not sure how it will come out here though. Does this look similar to your diagrams Ron? If I follwed your previous post right there does look to be a "tee" with one end open.

[ron69912t]

Craig:
That is the part I was referring to. My Parts book calls out #49 to be P/N 901.201.619.22 and they call it a "Transition Piece".

Having a heck of a time locating a source for some Activated Charcoal (aka Carbon).

The hoses, #50, 51 & 54 are each called "Air Bleed Hose".

Hose #56 is not on the 1969 USA version 912

Ron
Ron

[craign]

Ron,

I was wondering why this Parts CD came up "part number unknown" when I clicked on it. They call the Tee and "intermiediate piece" but either way 2 ends are open huh?

I guess I get to hand trace mine out tonight.

Craig
69-912

[craign]

Ron,

I have that tee in my vent line, 1 line goes to the tank just to the left of the sender unit and the other down the side and out the bottom just behind the washer fluid tank. The tee that I have is a "Y" shape and it is in the vent line to the bottom of the car and one end is just sticking out with nothing on it.

Craig

[cgarr]

My 69 has the exact setup so that must be the way they came. Gas fumes always drop to the lowest point so an open Y mid way should not be a problem, My Y points back towards the dashboard, maybe its a sort a vent so that the tube hanging out the bottom of the car cannot draw a vacuum on the tank when moving and stop your fuel flow to the engine.

Craig

[craign]

My "Y" tube points back toward the dash also.

Craig

[Scott Douglas]

Ron
You might try getting charcoal at a tropical fish store. I think they use it in the filters for aquariums.
Scott

[craign]

Fish store is one possibility another might be Home Depot or someplace like that. I have a charcoal cartridge that I use on the water inlet to my ice maker. It is about 4" long and maybe 1.5" in diameter.

Craig

[Roland Kunz]

Hello

The t connector ist there as the vent line coming from the brake fluid canister joins in there.

You will find a explanation from that all on the 911 board.

However US versions normaly should have carbon canisters added to the system.

Grüsse