Comment

Comment by Jason Edge on May 14, 2020 at 2:20pm

Chrstian,
It prevents siphoning? Ever stick hose in a gas tank and drain it out, or perhaps stick a hose pipe in an above ground pool and as siphon it out? It stops the ability of the gas to pour out if on an incline and enough gas in the tank. Another way of thinking about what it does, drink a soda thru a staw and stab a hole thru it with a pin. Point is air is supposed to go in this vent pipe, and the hole just helps keep gas from siphoning out if it does run over and out the  pipe.

Comment by Christian Doerk on May 13, 2020 at 5:40pm

I have this hole too, but even I tried to figure out what it does exactly, I still have no idea. Why insert a tiny hole up there will do it better than the larger opening of the pipe itself?

Comment by Jason Edge on November 15, 2012 at 9:12am

Note vent hole on top of vent pipe. Per April 1964 Seviceman Bulletin Page 19, this .050" hole was added on AC equipped cars beginning with engine # 060960 and non AC equipped cars beginning with engien # 060242 to reduce fuel loss when filling tank and braking.  The pipe was also moved to a more upward position via a special clamp. On my car I simply bent the existing metal clamp back the other way to force the pipe in a more vertical position.

Here is link to the serviceman bulletin: http://6364cadillac.ning.com/photo/april-1964-19?context=album&...