Fuel tank venting??

[Red's '72 Dart]

OK so what is different in the car from factory? Have you removed the "carbon can" evap control system? That WAS the vent originally.

You MUST be careful to get "whatever is there" (or whatever you build) ABOVE the fuel so it will not siphon. Originally, there was a 1/4" tube coming from tank up to engine bay beside the main fuel tube. That IS (was) the vent, and originally had an anti-spill valve in the end of that tube.

We need to know what you are changing

I have a '72, the anti-spill valve in the 1/4inch vent line failed. I had to remove it so my tank could properly vent into the charcoal canister. Do I have to replace that anti-spill valve?

 

[Joel Chapman]

What if you have a single line coming off the tank to a breather valve on yo passenger valve cover? It’s a 71 Dodge Dart 318 with no charcoal can on it. I was trying to swap that breather cap out for something different. Do I need to do the 69 filler neck vent as already discussed in this thread?

 

[67Dart273]

I have a '72, the anti-spill valve in the 1/4inch vent line failed. I had to remove it so my tank could properly vent into the charcoal canister. Do I have to replace that anti-spill valve?

I would say no so long as it's vented. "It might be" that if you ever park downhill on a "San Francisco" street with the tank clear full, that it could siphon some fuel out I don't know The vapor separator is sposed to take care of that I believe.

 

[67Dart273]

What if you have a single line coming off the tank to a breather valve on yo passenger valve cover? It’s a 71 Dodge Dart 318 with no charcoal can on it. I was trying to swap that breather cap out for something different. Do I need to do the 69 filler neck vent as already discussed in this thread?

Frankly if you are able to duplicate the 69 style vent, they are dirt simple and work great. Otherwise if you still have the 1/4 line up front, as long as it's "high and open" you should be OK. Some guys on here suggest plumbing it into the air bonnet, which sounds like "how it was."

 

[67Dart273]

Sure nuff 71 evidently did not (yet) use a carbon can. Bear in mind these systems changed every darn year almost. The fuel caps are especially a zoo of "differences" Diagram out of the 71 FSM

 

[kursplat]

i know it wasn't the original question by the OP, but, since Tanks Inc considers this a rollover vent to "Keep Fuel from coming out of the vent when turned upside down in case of an accident", does anyone run a rollover valve on their stock tank vent and how did you plumb it?

 

[Joel Chapman]

Sure nuff 71 evidently did not (yet) use a carbon can. Bear in mind these systems changed every darn year almost. The fuel caps are especially a zoo of "differences" Diagram out of the 71 FSM

View attachment 1715529557

Mine is set up like that except I don’t have the four tubes on one side, just on tube in the front of the tank but it follows from there up the same as this diagram. I’m just trying to use a different crankcase cleaner since I’m not using the other lines off of the cleaner any more. Only one I couldn’t figure out what to do with was the fuel line.

 

[famous bob]

Mine is set up like that except I don’t have the four tubes on one side, just on tube in the front of the tank but it follows from there up the same as this diagram. I’m just trying to use a different crankcase cleaner since I’m not using the other lines off of the cleaner any more. Only one I couldn’t figure out what to do with was the fuel line.

I have a non vented flip top cap on my 68 fastback . It has the recirculating tube to the near top of the filler tube , which I ran down to the tank seam and towards the back of the car , some came like that . The new tank I installed about 9 yrs ago came w/ a vent tube sticking out of the pick up assem. right beside the fuel feed . I ran this tube around the gas tank and up thru the floor of the trunk /up hi w/ 2 coils in it and back down thru the trunk floor ,just long enough to be in the air stream , but not seen. It doesn`t puke fuel on fill up, (like a new 68 barracuda would back in the day) , never had a problem w/ it , and I do run a 1200 cfm throttle body on a 505'' engine , never have had fuel come out anywhere , been working for about 9 yrs.
no need for any roll over valve , or vent lines to anything else , those 2 small 1/4'' o.d. vents will probly handle about situation. -------------jfyi