Venting the Fuel Cell Without Fumes

[Guest 305240]

I plan on running my 72 tank. But I think I'll plug a few lines and run a vented cap. I've run these style on 55 chevys for years and hever had the slightest hint of gas fumes. It seems to me now with the emissions laws, more and more garbage is hung on the tank with a half dozen or so lines going everywhere. In this case, I feel the older and simples system will work the best. I've seen filler necks with vent tubes conning off them and venting to the atmosphere. Who's gonna know unless you tell someone?

[Dan Juday]

Dan, do you have any reference for the GM valve, such as part name, car model and year, part number...? Thanks

 

Sorry, no part number. My motor came out of a '91 f-body tpi. My bet is it's the same vent valve for many GM cars of the same era.

 

It's a white plastic deally a little bigger than a golf ball. Has a 3/8" barb fitting on the bottom and an arrow head like thing on top than snaps into a grommet on the body that it hangs on. I broke the arrow head off mine so I just mounted it on an L bracket with a half inch hole. Vent hose goes up through the hole, plugs into the valve, put a hose clamp on and it's mounted.

 

GM mounted it above the tank so I did the same. Mine fits in between the rear stock steel fender and the fiberglass one on the right side. The bottom of fenders are open so any discharged vapors vent to the outside of the car. If I didn't have the fat glass fenders I don't know were I would mount it.