gas tank vent

[steitsma]

I just got a used tank to replace a 92 that leaks.  The old one just had 1 vent from the gas cap and the one I just got is from a 95 I think but there looks to be 2??  The other one is turned 90 degrees on the opposite side, anyone know if this is a vent or something else??

[average]

pics, dude. The 2 tanks you speak of are one in the same unless you're across the pond. 

[ned from PA]

I keep reading about gas tank vents, but, by my reckoning, the outlet to the atmosphere at the base of the gas cap is an overflow hose and not a vent.  Venting of the tank occurs via the cap itself, which allows a small flow of vapor to pass through it.

If you overfill your tank at the gas pump, the extra gas will spill out the hose instead of soaking your nicely painted tank.

[adidasguy]

The hole and hose on the tank is overflow and for water entering around the cap.

The part of the cap that actually seals the gas inlet should have a very tiny hole on the order of 1/64". That would be the vent. Too small for any gas to really leak out but small enough for air. If that gets plugged, a tank could develop a vacuum and the engine might seem starved for fuel.

[steitsma]

see attached link for pic

www.gstwins.com/photogallery/displayimage.php?album=lastup&cat=0&pos=0

[gregvhen]

well the one closest to the petcock is your drain right under the gas cap. dont know what the other is for.

[steitsma]

yeah, I don't know what the other one is for

[adidasguy]

Where does it go? Run a piece of string or fine wire through it and find out where it comes out. Look in the tank with a flashlight and what do you see?
Maybe its just an extra drain for the tank for water and sediment?

==== update due to boredom and being on happy pills ===============
OK, on crutches so either look in books, watch Sponge Bob or buy stuff on ebay. I chose the former.

Seems there is a vent to the tank for California models called "Evaporative Emission Control System". Diagrams are in the Haynes and Clymer manuals. I doubt that is important but someone who is a be a carb/fuel system expert to tell how important that is and how to disable that system if you have a tank without that extra vent. Diagrams do show it coming off at a 90* angle. Regular fuel cap drain comes straight down off of the tank.

Hope this helps. Someone else care to chime in?

[The Buddha]

Its the CA crap. Doesn't vent ... doesn't do nothing.
Cool.
Buddha.

[steitsma]

Ok, thanks everyone, I will not bother running a vent line to it then!!