Fuel lines

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Ok, Next question RRR, how do you make the original gas cap vented?
I'm following this because my charcoal canister is gone and the line is just hanging out in the engine compartment. Lol. Mine is a72 Scamp. Thanks Steve

I simply get a 1/16 drill bit and go right through the under side of the cap. Not the outside, but the under side in such a way as to miss the sealing area, otherwise it will not vent. Just flip it over and look at it. It's pretty obvious where to drill. Done a lot of them like that through the years.
 
I simply get a 1/16 drill bit and go right through the under side of the cap. Not the outside, but the under side in such a way as to miss the sealing area, otherwise it will not vent. Just flip it over and look at it. It's pretty obvious where to drill. Done a lot of them like that through the years.
Then I can plug the vent tube at the gas tank and get rid of the line going back to where the canister used to be?
 
Then I can plug the vent tube at the gas tank and get rid of the line going back to where the canister used to be?

Sure, but keep in mind, the way I am describing to vent the cap is a 24/7 vent, it's not like a vented cap with a valve that builds pressure and vacuum and then vents. It will be vented all the time. I don't know why you would want to do away with that vent line though. I would rather use it for a liquid fuel return.
 
Sure, but keep in mind, the way I am describing to vent the cap is a 24/7 vent, it's not like a vented cap with a valve that builds pressure and vacuum and then vents. It will be vented all the time. I don't know why you would want to do away with that vent line though. I would rather use it for a liquid fuel return.
Ok, I'm gonna have to reread the post. I think you showed us a three nipple fuel filter. That is what I should connect the return line to correct? Thanks and sorry dartfreak for overtaking the post.
 
Ok, I'm gonna have to reread the post. I think you showed us a three nipple fuel filter. That is what I should connect the return line to correct? Thanks and sorry dartfreak for overtaking the post.

Yes, that's correct.
 
Ok, I'm gonna have to reread the post. I think you showed us a three nipple fuel filter. That is what I should connect the return
Then I can plug the vent tube at the gas tank and get rid of the line going back to where the canister used to be?
@dartfreak75 here's the uncle tony video about using the using the 3 nipple filter with the vapor line:


Check and see if you already have a vent above the sending unit? I'm going out in a little while and will check mine but my tank appears to be unexact repo. There is a vent nipple visible in this aftermarket tank:
1971-76 Dodge Dart / Plymouth Duster Gas tank

Somebody correct me if I'm wrong please.
go back to 38 and watch that video that is what rusty is talking about this is how I'm gonna do mine all you would have to do is run a 1/4 fuel hose from the line that goes to the canister to the third nipple on the fuel filter. That like goes back to the top of the tank
 
Ok, I'm gonna have to reread the post. I think you showed us a three nipple fuel filter. That is what I should connect the return line to correct? Thanks and sorry dartfreak for overtaking the post.
You good dude. I like when people get Involved in these type of threads and learn with me lol. Hope this thread helds you as much as it has me.
 
Got the tank out this morning. Another one of those 1 step forward 2 back situations. Remember the rust in the trunk I found? Well I really found it!! The entire hanger ripped out when I tried to loose the j-bolt! :BangHead: Good news is I got the tank and sending unit out. I'm gonna clean up the sending unit. Is the little screen filter in the end removable and replaceable? I didn't mess with it a whole lot I didnt want to break it too. Haha

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I guess what has me confused in all this is if you use the old charcoal can line as a vapor return to the tank, don't you still technically need a vent to atmosphere somewhere? Or does the cap function as the vent? I'm reading lots of conflicting information about whether the 72+ caps are true vents.
Vented gas cap?

EDIT: Maybe not "conflicting" information, but I'm having trouble understanding it anyway.
 
I guess what has me confused in all this is if you use the old charcoal can line as a vapor return to the tank, don't you still technically need a vent to atmosphere somewhere? Or does the cap function as the vent? I'm reading lots of conflicting information about whether the 72+ caps are true vents.
Vented gas cap?

EDIT: Maybe not "conflicting" information, but I'm having trouble understanding it anyway.
Yes you still have to vent the tank. The idea that I had was to run a line out of the top of the tank but rusty's Idea is alot easier you just drill and vent the cap. Or buy one that is vented already it does the the same thing as my idea just much easier. When gas gets hot it expands have you ever seen a full gas jug at the end of the day when you been mowing all day? It's all swole up thats the same thing your tank will do without some sort of vent. The return line simply relifes that same pressure that's made at the fuel pump and in the fuel lines and gives it a place to go. Back to the tank.
 
What i've read so far seems to indicate that the 72+ gas caps relieve excess pressure, but are not necessarily designed to allow air to enter the tank as the fuel level depletes.
 
What i've read so far seems to indicate that the 72+ gas caps relieve excess pressure, but are not necessarily designed to allow air to enter the tank as the fuel level depletes.
Idk but I know for a fact my 75 didnt vent it good enough. When I would fill up completely it would hiss and build pressure and eventually blow it back out of the filler tube.
 
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