72 Beetle / Fuel Vacuum Hoses / Fuel Gauge Voltage Stabilizer

Jul 15, 2009 1 Replies

Hello List!



Ive got a 1972 VW Beetle



A few questions that John Muirs Book has shed little light on for me.



When I open the gas cap should it be sucking air? Ive got a vacuum in there. Its been doing this since I replaced all the gas vapor recycling hoses. They were all original and cracked. I used vacuum hose until I am advised on something else. An annotated image of the front boot - fuel hoses.

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The gauge indicated 1/4 tank when I ran out of gas. Instead of bending the pivot point / guage needle I opened up the voltage stabilizer and spread the windings apart. This resulted in the needle going way past full and I have only used a gallon so far. By the time I get to empty the gauge may reflect more accurately? Where do I find a replacement voltage stabilizer?



There is a toggle switch on the duct work coming off of the shroud. What is this? An annotated photo of the engine compartment -

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Aloha Eric


Congrats on your find.

No telling what the toggle does/did; it's non-stock. Follow the wires and report back.

Your fuel system has been "hacked". Go:

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on #25-10 and #25-20 Canister #1 is under the right rear fender/wing. Pipe #8 runs to the front of the car where it connects to the piping under the bonnet.

Hose #15 supplies air to the canister to force vapors out to the air cleaner and ALSO to prevent vacuum in the tank.

If vacuum forms, the tank could collapse and/or the engine will starve for fuel at highway speeds.

If all the bits are missing, the best you can do is leave a small vacuum hose from the tank open to atmosphere (outside the car) to vent the tank.

The stabiliser/vibrator is available from most any parts house:

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Speedy Jim

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