Fuel spilling out the stock gas cap...fixes?

[heywier427]

I read a bunch about it, and short of converting over to a newer cap/filler neck, there are no fixes.

 

Anyone think this may work?  Or at least help a whole lot.

 

 

http://mikeschevy.com/57-1957-chevy-gas-tank-fuel-filler-tube-check-valve/

 

 

Diameter is too much at 2-7/16 o.d.  But its an extremely simple design to make up out of 2"

 

Put it in right at the filler neck so the gas nozzle pushes it up/open.  Im thinking slide it in and hose clamp it in place from the outside.

 

Seen a bunch of rollover type ball/float valves, but I dont think they will work due to the horizontal angle of our filler tube.

 

Any other ideas?

 

 

[Draker]

That is a interesting idea if you are stuck on staying with the stock setup. 

 

However, the Mazda fuel neck retrofit is a great mod and you can fit newer nissan caps.

[bananahamuck]

That is a interesting idea if you are stuck on staying with the stock setup. 

 

However, the Mazda fuel neck retrofit is a great mod and you can fit newer nissan caps.

 

And done with cheap tools you probably already have around the house.

[heywier427]

Gonna make my own design.  Will be better than the one pictured.

 

Vertical delrin flap pushed/held down by a light spring.  Seated on a small step to stop/seal it.  Inside of a 2" diameter tube.  Slide it into the filler tube and hose clamp in place.

 

2-3" inside the filler neck.  Pushed open by the filler nozzle.

 

A project I will never get to...

[heywier427]

And yes, stuck on the stock looking filler.

[datzenmike]

Gas can't spill out if the cap has a good seal. Some caps vent but only inward others are sealed tight. Check your rubber gasket.

[heywier427]

I tried.  Its new.  I used a few different types of sealing surfaces, but they all leaked.

 

Im also being anal.  When I say "leaked", its a full tank of gas, driving like a loon, and it was a single bead going down the body.  But every trip.  Its just annoying.

 

I got an nos one to seal almost all the time (by stacking 2 seals), but the new repop one wont.  The metal is not strong enough to keep the compression tight.

 

The easier thing to do is send the nos one to get anodized.

 

I also have a tough time with that type of twisting motion with my thumb.  Many boxer fractures under its belt.  Even with my new cars/caps.

 

I just like inventing/tinkering and starting 13 projects in the middle of my 13 other projects.  You know, like the rest of us :)

[datzenmike]

What about the surface the rubber seals against? Could be dented? Had a rad cap like that ran a flat file over it.

[heywier427]

Wish it was that easy.

 

The surface looked flat, but I filled it, then sanded/polished it.

 

That made it much better, but still a bit of a weep.

 

Im also being hindered by the fact that I have a 2 stroke and mix the oil in the tank.  The oil helps it find its way out/hang around, instead of just evaporating.

[datzenmike]

A two stroke 510?

 

The gas tank should not leak, they didn't design them this way.

[heywier427]

Rotary  :thumbup:

 

They should not leak, and of course they were designed not to, but many people complain about this issue.  And its not just Datsuns.  Many 50-70's cars with this simple designed cap and a damn near horizontal filler tube has/had slosh issues.

 

Its one of the main reasons the american cars moved the filler from the rear end of the cars, to the sides.