TECH TIP Technical Index

Violent Fumes

by Mike C. -

No, Im not talking about that new-age rock group your mother told you not to go see. Im not even talking about the kind of stuff floating in the air at one of their concerts. This has to do with the gasoline odors that nearly every one of us gets a whiff of from our VWs as they leak fuel from one of the fuel lines. The newer (68-up) VWs are especially prone to these smells since they are equipped with early fuel evaporation systems and nearly twice the amount of fuel lines than the previous models. The dash panels on our VWs are very open to the front compartment, with all the holes for wiring, hoses, and radio. If you dont believe it, just drive it on a cold day and youll quickly find out how breezy it can get inside the car with the windows up! In this article, I will tell you how to have a VW that smells more like flowers than raw gasoline.

Youll need

  • 13mm ratchet/socket
  • Hobby knife or utility knife
  • 2 - fuel filters
  • 10 - "-1/2" hose clamps
  • 10 ft. - 6mm cloth-braided fuel line
  • 6 ft. - 4mm fuel line (for 68-up evaporative emissions)
  • Fuel cap gasket
  • Fuel filler rubber hose section
  • Sending unit gasket
  1. To begin with, disconnect the battery.
  2. Now go to the source of the fumesthe gas tank area. It will be easier if you work with a tank that is nearly empty.
  3. First, make sure the tank itself is not leaking. If it is, you need to either replace it with a new one or make some kind of repair to the old one (see article on gas tank repair).
  4. Grab a 13mm ratchet/socket and remove all the hold-down bolts around the tank.
  5. Unplug the sending unit wires from the tank. If you have a 68 or later VW, youll have to remove the rubber neck that connects the tank to the filler on the outside.
  6. Lift the tank up and pull the fuel line off the tank. Have a small bucket ready to catch any remaining fuel spillage.
  7. Cut some new 6mm fuel line the same length as the old line, push it on the new fuel filter, and install all of that on the fuel tank and main fuel line, with clamps at each connection.
  8. Slap the fuel tank back on and bolt it down. If you need a new rubber connector for the fuel filler neck, put one on now, with new clamps.
  9. Also, replace the sending unit gasket with a new one.
  10. If you have several smaller fuel lines coming out of the gas tank (68-up), get your new 4mm fuel line and start replacing the old lines one at a time. Since these lines do not actually pass liquid fuel, theres no need for hose clamps unless you feel the urge. All the fuel lines are supposed to fit tightly on the fittings.
  11. If the old hoses are really stuck, especially on plastic fittings, use the sharp hobby or utility knife to cut them off.
  12. Finally, put in a new fuel cap gasket (really important for 67-down). This wraps up things under the front compartment.
  13. Going to the rear, all of the fuel lines will be the 6mm size.
  14. Get under the car (supported by jack-stands, not the jack itself!) and replace the main rubber fuel line from the tunnel to the engine.
  15. Now replace all the fuel line and fuel filter at the engine, using clamps at each connection. It is especially important that you keep tabs on the condition of the fuel line in the engine compartment, as old cracked fuel line is a major cause of engine fires.
  16. This is a good time to plug up all those holes in the dashboard, as well. If there is not going to be a radio, get some kind of block-off plate that fits tightly in the hole that was left. You might consider one of those after market covers you can install behind the dash in the front compartment. This will help keep unwanted air and any leftover fumes from getting inside. Those of you with 73-up Super Beetle sedans and all convertibles will have a bit easier time plugging up holes in the dashboard, as there are very few holes that wiring has to pass through.

When you get new fuel line, stick with the stock cloth-braided stuff thats made in Germany. The plain rubber hose you get thats made here will not have the proper fit and may cause premature leaks and fumes, which you wanted to put to a stop in the first place! Be a bit more careful when you fill up with gas, so you dont spill any in the car or on it. Besides causing a smell, it stains the paint and is a potential fire hazard.

Now you wont have gasoline fumes ruining that romantic moment at the drive-up bratwurst burger joint!

Your VW Maniac and tech specialist,

Mike C.