"karl gruber" wrote in message
...
****There is only one vent, under the left wing*****

Not on my high wing Cessna. There are vents behind the struts for both
wings.

Karl
"Curator" N185KG

What model?

The 172S has the left tank vented behind the wing strut and right tank
vented to left tank.
The 172M has the left tank vented behind the wing strut and right tank
vented through the fuel cap.
Both according to the respective POH (and backed up by memory).

Of course, Cessna makes other models too, some of which aren't even 172's!

Eric