Fuel tanks

[Richard Farrant]

Originally Posted by Lynn Eades

I too can state the obvious; The MAIN purpose is to allow air into the tank to stop it collapsing as the fuel is drawn off. BUT... when there is vapour pressure in the tank, does it lift the ball and close the valve?

Well, I do not see how it could have been a spark arrestor, that is something you normally get on an exhaust pipe to stop sparks escaping, so I was just pointing out the true purpose of the ball valve, in case you were unaware.

It is doubtfull that vapour pressure would lift the ball enough to close the valve, as it would have to be a surge of pressure, where as vapour would be a slow build up. Only my thoughts though,