Adding a vapor line to your fuel filter

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Slantsix64

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Hey guys so I got a 67 abody wanted to run a vapor line from a 3 nipple fuel filter, question is were do I run it too? I don’t have a vapor canister in my trunk? Thanks in advance
 
I dunno if this is my answer but if I had that later style fuel sending unit with the extra connection can run that return line into there?
 
If you are talking about the fuel filters that were used in the 80's with a third nipple that comes off the side of the "can", that isn't for a "vapor" line. It's for a return line to the tank. Raw fuel will come out of that line. It should be routed to the tank...not a charcoal canister.
 
If you are talking about the fuel filters that were used in the 80's with a third nipple that comes off the side of the "can", that isn't for a "vapor" line. It's for a return line to the tank. Raw fuel will come out of that line. It should be routed to the tank...not a charcoal canister.
Okay so I would be able to tee that back into the fuel tank using a fuel sending unit with the extra fitting, this will help with my hot starts? Tried the heat insulated don’t like how it raises my carb up.

8A1CA197-CAA6-4B92-B8A4-88D006CBE078.jpeg
 
Okay so I would be able to tee that back into the fuel tank using a fuel sending unit with the extra fitting, this will help with my hot starts? Tried the heat insulated don’t like how it raises my carb up.

View attachment 1715855661
I did this on my 318 Scamp. Instead of running it to the charcoal canister I ran it to the 3rd nipple on my fuel filter. It's worked well without any problems.
 
I did this on my 318 Scamp. Instead of running it to the charcoal canister I ran it to the 3rd nipple on my fuel filter. It's worked well without any problems.
Did it eliminate hard start after driving and letting it sit for 15 mins
 
Did it eliminate hard start after driving and letting it sit for 15 mins
I wouldn't think it would eliminate that. That's normally caused by the fuel in the carburetor getting too hot or the fuel turning to vapor in the intake manifold. The latter of the two there's not a lot you can do about. But if the fuel is getting too hot in the carburetor, you can run a thick insulator gasket to mount the carburetor to the intake.
 
Did it eliminate hard start after driving and letting it sit for 15 mins
That's a good question because my intention was to eliminate the charcoal canister and not have fumes in the engine compartment. It did that and it starts up instantly on a cold start but it doesn't start as quickly on a warm start. That could be carb related and the car has been put away for the winter so I'll have to do some sorting out in the spring.
 
Okay so I would be able to tee that back into the fuel tank using a fuel sending unit with the extra fitting, this will help with my hot starts? Tried the heat insulated don’t like how it raises my carb up.

View attachment 1715855661
You either have to use something like that sender or create a second line fitting into the tank. I don't recommend this for faint of heart, but I used an awl to punch a hole into my tank, flooded the tank with a CO2 bottle off my MIG welder, and then brazed a piece of tube into the hole

On the wix filters, there are several part numbers, for 5/16 or for 3/8 on the main tube, or for inline or 90 exit for the return. Be sure to run the return "at the top" of the can or follow directions for positioning. On the "inline" return, either mount the filter horizontally with the 1/4" return at the top, or mount it vertically with the 1/4" exit pointing up
 
I wouldn't think it would eliminate that. That's normally caused by the fuel in the carburetor getting too hot or the fuel turning to vapor in the intake manifold. The latter of the two there's not a lot you can do about. But if the fuel is getting too hot in the carburetor, you can run a thick insulator gasket to mount the carburetor to the intake.

But wouldn’t that 1/4 outlet allow the fuel pressure to vent back into the tank instead of having it stay in the fuel pump and line to boil after shut off?
 
But wouldn’t that 1/4 outlet allow the fuel pressure to vent back into the tank instead of having it stay in the fuel pump and line to boil after shut off?
ummm....what?
 
You either have to use something like that sender or create a second line fitting into the tank. I don't recommend this for faint of heart, but I used an awl to punch a hole into my tank, flooded the tank with a CO2 bottle off my MIG welder, and then brazed a piece of tube into the hole

On the wix filters, there are several part numbers, for 5/16 or for 3/8 on the main tube, or for inline or 90 exit for the return. Be sure to run the return "at the top" of the can or follow directions for positioning. On the "inline" return, either mount the filter horizontally with the 1/4" return at the top, or mount it vertically with the 1/4" exit pointing up
Okay cool, yeah I do have that fuel sender with that extra outlet, hopefully this helps my hot starts after shut off.
 
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