Can anyone recommend a decent gas cap for a VS fuel tank that will not leak?
I've had two and both leak. And yes, both were always screwed on properly.
Many thanks.
Attachments
Images (1)
Original Post
Replies sorted oldest to newest
Can you see a vent line from the tank? That allows gases that build up (due to over filling or heat build up) to escape as gases - and not force raw gas out from the tank gasket.
I've also had 3 caps go bad. I've been getting them at my FLAPS, but I'm all ears on this as well.
Add an extra neoprene gasket to the underside of the cap ?
Simple answer - no, I haven't found a replacement cap that doesn't leak.
But, I was able to seal the cap that came with the car.
When I first got my VS, there was a strong smell of fuel on the first few hard left turns after topping up the tank. This turned out to be a poorly routed vent line, but that's food for a whole other thread.
In the course of solving this, I found that the 'unvented' cap supplied by VS actually had lots of little 'vents' it shouldn't have had. I first replaced the gasket with a nice neoprene one, but that wasn't what was leaking. It was the design of the cap - as per this photo.
If you pull off the gasket and pour a few drops of alcohol through those large slots, you'll see where the alcohol starts leaking out around the rim. I plugged up the little gaps around the rim with some glue, let it dry well, and that seems to have stopped the leaks. It's probably smarter to use JB Weld as a sealant, but three years down the road, I'm still OK.
Attachments
What a great solution. Thanks, Mitch! 
Many thanks to Bruce, Alan and Mitch.
Bruce, thanks to similar suggestions made by you I was able to fix the vent line problem a few months ago.
Mitch, I agree with Stan and will try your solution on the original VS gas cap.
Alan, your suggestion to add an extra neoprene gasket might very well correct the problem I've been having with the second gas cap. It was purchased from a different builder and it's completely different from the first one that came with the car.
Attachments
Images (1)
If the tank is vented - you shouldn't need a vented gas cap. Shame there isn't a cheap source for plastic charcoal filled expansion boxes to absorb gas fumes (like OEM VWs - but they were metal and rusted out).
Any source other than home made for the gasket?
WOLFGANG posted:If the tank is vented - you shouldn't need a vented gas cap. Shame there isn't a cheap source for plastic charcoal filled expansion boxes to absorb gas fumes (like OEM VWs - but they were metal and rusted out).
You could go to a salvage yard and get a plastic one from a more modern car.