EngineerDoug
Well-Known Member
Hello all,
I have a question about stock fuel tank venting. My tank is a repro '68 installed in a B body. I have both the external vent lines connected - the short one that runs up to the shock mount crossmember area, and the the long one that runs up into the trunk and then loops up and down into the frame rail.
I am experiencing the common issue of fuel smell once the car is parked in garage. It happens with a full tank, particularly on a warm day. The fuel is being forced out the vent line that exits into the frame rail. It's not just vapor, which leads me to believe the line inside the tank is below the fuel level.
I understand that the two tank vent lines inside the tank are different - one is short and one long. I need to look inside with a borescope to confirm which is which, but my basic question is, why did the factory set it up this way? Did they anticipate that the car might be parked on an incline? This arrangement would ensure that one of the lines would be above the fuel level, I would think.
But what about when the car is parked on a level surface? The behavior I am seeing suggests that both internal vent lines are below the fuel level.
And why would the factory setup include a very short line outside the tank, and a very long one outside as well? I guess I am just trying to understand the logic of it, as the fuel puking is a problem with an attached garage.
Thanks.
I have a question about stock fuel tank venting. My tank is a repro '68 installed in a B body. I have both the external vent lines connected - the short one that runs up to the shock mount crossmember area, and the the long one that runs up into the trunk and then loops up and down into the frame rail.
I am experiencing the common issue of fuel smell once the car is parked in garage. It happens with a full tank, particularly on a warm day. The fuel is being forced out the vent line that exits into the frame rail. It's not just vapor, which leads me to believe the line inside the tank is below the fuel level.
I understand that the two tank vent lines inside the tank are different - one is short and one long. I need to look inside with a borescope to confirm which is which, but my basic question is, why did the factory set it up this way? Did they anticipate that the car might be parked on an incline? This arrangement would ensure that one of the lines would be above the fuel level, I would think.
But what about when the car is parked on a level surface? The behavior I am seeing suggests that both internal vent lines are below the fuel level.
And why would the factory setup include a very short line outside the tank, and a very long one outside as well? I guess I am just trying to understand the logic of it, as the fuel puking is a problem with an attached garage.
Thanks.
