Anybody got a clue?

[chief]

I've got a 76 spider and love it. I have noticed though when I fill up it will run very poorly for a little while so I figured trash in the tank.
Guess what, no trash. I have already replaced the fuel filter, cleaned the small screen in the carb and everything else I could think of. Then I noticed something mounted to the back of the trunk; what it is, don't know and hope someone out there has a clue.
As you look at the pics there are several cracks in the body of the unit, could this be my problem? allowing air into the system?
Clue me in and let enlighten me. Purpose, name and ect...

[halg]

My parts book calls it a two way valve pn4226204. The picture shows a second hose connection where the hole through the side of yours is. The book says that it was only used on 76-77 models.
Hal

[SLOSpider]

If it hooks to the fuel lines it looks like a roll over valve. Does it rattle?

[mdrburchette]

Evidently it's a one way valve for the rest of the year models, according to my parts book. It's supposed to keep the fuel tank at a certain pressure:

[halg]

The pictures in my parts book show a different looking valve for the one way, but anyway??? I have one its yours for an address.Mine had black trim around the mount. PM me.
Hal

[ventura ace]

Here's an old post (below) about the valve that you are describing. It appears that one of the connections is broken from your valve:

http://fiatspider.com/f08/viewtopic.php ... lve#p18882

Alvon

[chief]

First off thanks guys for the responses, and I apologize for not be at the keyboard. My mother in law has had some recent heart trouble and we had to leave at a moments notice, hence my failure to reply.
You guy's are sharp, the hose barb was broken already hanging on by a thread so it came off when I removed it to take picks (thats why I just cut the other side).
And no it didn't rattle, it feels solid inside, hard to push air through.
could this be the source of my trouble?

[BEEK]

it is a fuel vapor vent valve, designed to release vapor from the tank to the charcoal cannister, which is under engine vacuum,

[chief]

Would this vapor valve cause the car to run irratic (like it is starving for fuel) at fill up? and at low fuel? Any where in between it runs great I thought it might be trash in the tank till I pulled it.