BrightGreenBug
Hey, I've got a 69 beetle and i've just had the fuel tank, fuel lines and carb replaced as there were rust issues and leaks in the tank which affected everything else. There is an extremely strong smell of petrol coming from the under the bonnet but there are no leaks in the tank. Anyone know if there is a reason for this or if its just standard? From the fuel cap there is only a small section of solid piping due to the position of the cap and the tank itself.
Cheers.
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MY72BUG
This is a fairly common occurrence with the old Beetles.  Some good places to start looking are the filler lines from the point where you put the gas in down to the tank itself.  The couplings being old tend to seep especially with a full tank.  Up under the cowl you may find a long plastic gadget with lines going down to the tank.  This was originally a device to deal with polluting gas vapours.  As they get old and brittle they become a primary source for gas fumes.  Do yourself a favour.  If you do have one there, yoink the damned thing off and plug all of the lines with short pieces of new line plugged with suitably sized bolts dipped in Neverleak.  This stuff comes in a red and yellow tube.  It gels in the presence of gas and is really great stuff even for actively leaking tanks.  Give this a try and see if it helps. 
I'd rather have a partial bottle in front of me than a partial frontal lobotomy.
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ainokea
Don't plug all the lines. You've got to have at least one open line to vent the tank. If not you could end up with an engine that dies intermittently because
of vacuum that is created inside the tank by the fuel pumps suction.

Ainokea
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MY72BUG
Your gas cap has a valve to allow for this.  Leaving any of the lines open under the luggage cover will nearly guarantee gas smells.
I'd rather have a partial bottle in front of me than a partial frontal lobotomy.
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ainokea
If the gas cap has a built in vent, why does the tank include one or two little vent tubes, depending on year and model, built into the tank?

You attach a piece of  vacuum hose to the tubing and run it out of the the luggage compartment to atmosphere.

Ainokea
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MY72BUG
On my 1972 type 1302 those lines used to go to a plastic device up under the cowl behind the windshield wipers.  I believe that it was there to control the polluting gas vapours created when the gas tank cooks under the luggage cover.  When it was all new it probably worked after a fashion.  When all of the plastic had decayed and the old lines had gone likewise the gas vapours under the luggage cover become very pronounced.  I spoke to an old VW guy up here about the persistent gas smell (even in a convertible) and he said to yoink out all of that vapour capturing crap, cap off all of lines and see what you get.  What I got was the end of the gas fumes.  If anyone else wants to follow my example, more power to them.  I am just trying to help them overcome a fairly common problem in the old Beetles.  Capping off all of these other lines has had no effect on the operation of my engine.  The venting in the gas cap allows air in to let the fuel out.
I'd rather have a partial bottle in front of me than a partial frontal lobotomy.
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olspeed
Depending on the year some VW's did or did not have venting caps. The only thing is with the vented caps is that they were designed to let air in and not pressure out.This was the reason for the vapor recovery system on the later model cars. my72bug is correct in saying that plugging all the lines and just using just the cap to vent the tank will work, but if you live in an area that has high temperatures this could be a problem with pressure build up in the tank. If you live in an area that does vehicle inspections this could also be a problem. As for my 66 it just has a hose that comes out of the top of the filler neck and runs out of the trunk dumping out over the steering box.(stock) On my 76 I got rid of the little plastic piece that is under the cowl and just ran a line back to the charcoal canister back under the rear fender... And now that it looks like the charcoal canister is rusting out I plan to just unplug the hose and let it end there.
Olspeed
66 Ghia 76 std Beetle
It's not a car it's a VolksWagon
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ainokea
I thought the vehicle in question is a 69. Late 71 models may have been equipped with the charcoal vapor tank under the right rear fender, but as far as I can remember, the 69 did not come with such a setup.

Ainokea  
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olspeed
Sorry to confuse but I was just stating that on my 76
 
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I got rid of the little plastic piece that is under the cowl and just ran a line back to the charcoal canister back under the rear fender... And now that it looks like the charcoal canister is rusting out I plan to just unplug the hose and let it end there

 So yes on the older cars(68 to 70) they didn't have the charcoal canister but they still had a device that vented the pressure (little plastic piece) from the tank but returned the fume laden air back to the tank. By the way according to my bentley manual it was 70 when they started to use the charcoal canister. But that does not mean that you are not right though on the late 71 date as the 69(my avatar) that I owned didn't have the vent system that is shown in the picture I uploaded and was totally different from the picture. It had a hose that came from the tank to the upper side of the filler neck, a tee type pressure valve(little plastic piece) was in the middle of that hose that had a small hose going off to the side that curved across the top of the cowl and then back down along the fuel tank an dumped out above the steering box. The opening in the drivers side that the picture shows the vent tube in was plugged and this was all oem VW.
Anyway what I was trying to say is that even if you do decide to plug all the little hoses the car should still run but... there really should be a way for the tank to vent because it will build up pressure and depending on where you live it could be enough to blow a hose off or push past the sending unit gasket(ya I know really old Bugs didn't have sending units or a gas gauge)
Olspeed
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66 Ghia 76 std Beetle
It's not a car it's a VolksWagon
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