Gasoline Leak (Vapor)

[neon]

Hello group, vive la coupe.

I have noted a stong gasoline odor in the garage, without an identifiable liquid leak. In a diagram in my 200 pg manual, I see that there is a crankcase vent system that routes vapor through an activated charcoal filter, but there is no detail or discussion of this leg of the system.
Has anyone had a similar problem, or used an approach to diagnosing an unknown gasoline or gasoline vapor problem that he (she ) could share ?

On another note I have owned this car for 1 driving season and cannot believe how much of a blast it really is.

Thanks for a most informative group
Dana

'73 CSi (L parts) Fiord Blue

 

[Honolulu]

use the search function. there are handfulls of ways these cars can send gas vapor smell into the passenger cabin... and "they all do that", or many of them anyway.

Crankcase vapors go from the valve cover directly to the air filter housing and are piped directly to the rear carb.

Gas tank vapors are routed to a plastic can over the right inner fender, then to the charcoal can under the battery and from there to the air filter housing, without valving as done on later cars. The sealing ring on the fuel tank sender, the connection between the braided line that goes forward, the line itself, the can over the fender, the charcoal can, are all guilty until proven otherwise.

A tiny bit of liquid gas can make a big smell. All fuel lines under the hood are guilty until proven otherwise, as are the tubular seals between the engine compartment and gutter forward of the windshield. There are penetrations between the two which might not be adequately sealed after all this time.

If you're running rich (and even if you're not) exhaust which finds its way into the trunk will get into the passenger cabin. Trunk seal is suspect.

And a couple dozen more, which you may find using the Search function.

 

[HB Chris]

Just one problem, he has CSI, and no vapor recovery tank in trunk.

 

[damienh]

Hi hope you don't have the problem I discovered recently, which was a tank leaking at the seam. I would never have noticed until I parked on a hill with a full tank of fuel and saw it dripping out. I'd had that smell for years, hoping it will disappear now.

 

[adawil2002]

I replaced the rubber gasket at the fuel pick up and the O-ring on the sender, that solved my fuel smell issue with a full tank.

 

[m5bb]

I ran the vent pipe that is coming out the side of the filler neck and would usually go to the plastic vapor canister over the right rear fender out the body below the filler neck.
That way the vapor from the tank is exiting the trunk.
BTW if your trunk does not seal well or pops open like mine does sometimes the vapors get sucked into the cabin and you will smell exhaust and gas.

Gary

 

[lloyd]

It goes without saying that if the smell is significant I would examine the entire length of fuel line/hose running from the tank, to the pump and then to the engine. Pull up the trunk boards that cover the spare and the tank for a closer look. Fuel line runs from the top of the tank through the body to the underside of the chassis.

There are at least two grommets (16121107262) that isolate the hose from the body, protecting the hose, and to a lesser degree, sealing the trunk interior from the exterior. If the grommets are compromised or not in place, the occupants may unnecessarily find themselves exposed to errant exhaust and fuel vapors. Although a pinhole exhaust leak is easy to overlook when it is outside the cabin, it should not be ignored inside the cabin. Pinhole fuel leaks, or weeping fuel, should not be overlooked under an circumstances, for obvious reasons. That said, as unlikely as it may seem, a full-over full csi fuel tank can naturally vent toward and below the rear bumper; however, if the above grommets are not in place, the peculiarities of air flow may still result in the scent of "oe d benzine."

It is worth mentioning that the fuel tank filler port and gas cap are segregated from the trunk via a rubberized membrane that contains "blind plugs." If either of these things is compromised, missing or poorly fitted, it is likely that the driver and occupants will be genuinely labeled "petrolheads." :| http://www.e9coupe.com/forum/showthread.php?t=16375

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