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MagmaJct · 09-17-2015, 02:20 PM

I'm not certain, but a 71 may use a one way vented cap. One that allows makeup air to enter the tank, but vapors cannot escape. The vapors are then routed to a charcoal canister.

It's common for people to remove the charcoal canisters for various reasons, typically having nothing to do with functionality issues.

Typically removal causes more problems than it solves. Make sure your tank is vented to prevent it from collapsing, causing mysterious "vapor lock" symptoms, or bulging and over-pressure problems, including diluted motor oil.

Regards,
Mike

09-17-2015, 02:20 PM	#3
MagmaJct Registered User Join Date: May 2008 Location: Mesa, AZ Posts: 281	Re: Gas cap I'm not certain, but a 71 may use a one way vented cap. One that allows makeup air to enter the tank, but vapors cannot escape. The vapors are then routed to a charcoal canister. It's common for people to remove the charcoal canisters for various reasons, typically having nothing to do with functionality issues. Typically removal causes more problems than it solves. Make sure your tank is vented to prevent it from collapsing, causing mysterious "vapor lock" symptoms, or bulging and over-pressure problems, including diluted motor oil. Regards, Mike __________________ I own 3 classic vehicles. 1971 LWB C10 Deluxe. 1974 VW Super Beetle. 1971 VW Fastback. The C10 and the Super Beetle run, the Fastback is just not there yet! Please visit my Super Beetle and Fastback profile on TheSamba.