2000 filler neck anti siphon spring--

[73mach/2000v-6]

Hi-

I just purchased a 2000 Mustang with a V-6 and have been doing a few things to it to get it in good running order. I'm new here and this is my first post. I was brought to this site by a search engine because I needed to replace the filler neck to tank gasket. I attempted to do so without dropping the tank like the post on this site said could be done, but unfortunately I broke off the plastic antisiphon assembly at the end of the filler neck. Luckily it did not fall into the tank. I priced the replacement filler neck and wasn't too happy with what I found for a price.
My question is--Is this antisiphon "check valve" required for any purpose other than stopping a fuel thief? I am thinking about re-installing the filler neck as is without this part. I do have the aftermarket lockable fuel filler door, so stealing fuel would still be difficult to do on this car without it. Would I have any other issues if I installed this filler neck without the plastic spring assembly at the end? Thanks in advance for any posts!

 

[wmburns]

FWIIW, the PRIMARY purpose of the check valve is to prevent a fuel spill in the event of a rollover.

The secondary purpose is to close off the filler neck when the tank is full. This activates the filling station's automatic shut off thus preventing fuel spills. Without a check valve, there is increased possibility of over filling and spilling fuel.

The 3rd purpose is to make it harder to steal gas.

Did you cut the old tank grommet completely off before removing the filler neck? If not, likely that is where the check valve was damaged.

OBTW, if you do drop the tank, this offers an easy chance to CLEAN it. The Mustang's tank is not really so hard to drop. Main thing is to empty it as much as possible.

 

[73mach/2000v-6]

Oops! That sounds important. I better get one ordered!!
And I did attempt to remove the filler neck without cutting the old grommet off.

Thanks!

 

[redsox1211]

Breaking off anti-siphon apparatus

I just performed this operation today with same result. The post on this site did not mention that tube will not come out of tank easily without damaging the anti-siphon. I shredded the plastic piece and spring. Cut it all off, filed off the sharp dges, and re-installed thru the new gasket. Everything works fine. Fuel maybe surges a little more than normal when filling, but who cares?