Gas tank liquid check valve

I have just discovered that my tank does not have the liquid check valve that normally attaches to the vent tubes coming off the left side. They are just capped off. A few questions:

1) How important is this part?
2) Where does it mount?
3) Could the fact that this ismissing explan why I get so much "splash back" when filling my tank?

Scott
75 CJ5

 

1) Depends on your definition of important. Its function is to keep fuel out of the vapor recovery system. You can read about the vapor recovery system in the 1975 FSM.

2) Under the wheel well on the rear passenger side - there is a panel to protect it from mud and rocks spinning off of the tire. There is a liquid check valve and an anti-rollover valve under there AFAIK.

3) Could be, but I think it's not likely to affect fueling - depends on whether all the other parts of the fillerneck are present and in good shape.

 

I found mine on the rear driver's side. Looked like a large glob of permanent mud. Stuck the garden hose up there one day and it slowly revealed itself.

Edit: I'd be amazed if the thing still worked.

 

1975 FSM? Where can I find that?

 

FSM=Factory Service Manual. EBay, there are also other sources, I'm sure someone with a better memory will chime in. A must have, if you ask me. way WAY better than Haynes or Chiltons.

 

for the splash back ,check the small vent hose by the filler hose. it's bent or plug up .