C172 fuel cap

"Ron Natalie" wrote in message om...
wrote in message ...
Thanks for the note. I've checked my vent tube and think it's in the
right place. My fuel caps are not original and I get a small amount of
blue streaking on the right wing aft of the cap.

The right cap on a 172 should be vented so that it only vents inward.

Those silicone rubber vent valves get old and leak, and will suck
fuel out of the tank. You'll see the leaky tank stay full longer than
the good one, as the lower pressure holds back the fuel.
Cessna won't sell the rubber valve. Got to buy the whole cap.
Cheaper than Piper, though.

Dan